diff --git a/dev-packages/browser-integration-tests/suites/feedback/captureFeedback/test.ts b/dev-packages/browser-integration-tests/suites/feedback/captureFeedback/test.ts
index 26ba665a418f..5d4ebe233c4d 100644
--- a/dev-packages/browser-integration-tests/suites/feedback/captureFeedback/test.ts
+++ b/dev-packages/browser-integration-tests/suites/feedback/captureFeedback/test.ts
@@ -44,6 +44,7 @@ sentryTest('should capture feedback (@sentry-internal/feedback import)', async (
   const feedbackEvent = envelopeRequestParser((await feedbackRequestPromise).request());
   expect(feedbackEvent).toEqual({
     type: 'feedback',
+    breadcrumbs: expect.any(Array),
     contexts: {
       feedback: {
         contact_email: 'janedoe@example.org',
diff --git a/dev-packages/browser-integration-tests/suites/feedback/captureFeedbackAndReplay/test.ts b/dev-packages/browser-integration-tests/suites/feedback/captureFeedbackAndReplay/test.ts
index 1590c68652a3..057b5d43a1c8 100644
--- a/dev-packages/browser-integration-tests/suites/feedback/captureFeedbackAndReplay/test.ts
+++ b/dev-packages/browser-integration-tests/suites/feedback/captureFeedbackAndReplay/test.ts
@@ -50,15 +50,16 @@ sentryTest('should capture feedback (@sentry-internal/feedback import)', async (
 
   expect(breadcrumbs).toEqual(
     expect.arrayContaining([
-      {
+      expect.objectContaining({
         category: 'sentry.feedback',
         data: { feedbackId: expect.any(String) },
-      },
+      }),
     ]),
   );
 
   expect(feedbackEvent).toEqual({
     type: 'feedback',
+    breadcrumbs: expect.any(Array),
     contexts: {
       feedback: {
         contact_email: 'janedoe@example.org',
diff --git a/dev-packages/browser-integration-tests/suites/tracing/envelope-header-transaction-name/init.js b/dev-packages/browser-integration-tests/suites/tracing/envelope-header-transaction-name/init.js
index e28325fcf78e..579523ee2015 100644
--- a/dev-packages/browser-integration-tests/suites/tracing/envelope-header-transaction-name/init.js
+++ b/dev-packages/browser-integration-tests/suites/tracing/envelope-header-transaction-name/init.js
@@ -1,4 +1,5 @@
 import * as Sentry from '@sentry/browser';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/browser';
 import { Integrations } from '@sentry/tracing';
 
 window.Sentry = Sentry;
@@ -17,4 +18,4 @@ scope.addEventProcessor(event => {
   event.transaction = 'testTransactionDSC';
   return event;
 });
-scope.getTransaction().setMetadata({ source: 'custom' });
+scope.getTransaction().setAttribute(SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, 'custom');
diff --git a/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/propagation.test.ts b/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/propagation.test.ts
index 9b83e882a739..cbb2c889edec 100644
--- a/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/propagation.test.ts
+++ b/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/propagation.test.ts
@@ -65,6 +65,7 @@ test('Propagates trace for outgoing http requests', async ({ baseURL }) => {
             'http.response.status_code': 200,
             'sentry.op': 'http.server',
             'sentry.origin': 'auto.http.otel.http',
+            'sentry.source': 'route',
           },
           op: 'http.server',
           span_id: expect.any(String),
@@ -89,6 +90,7 @@ test('Propagates trace for outgoing http requests', async ({ baseURL }) => {
             'http.response.status_code': 200,
             'sentry.op': 'http.server',
             'sentry.origin': 'auto.http.otel.http',
+            'sentry.source': 'route',
           },
           op: 'http.server',
           parent_span_id: outgoingHttpSpanId,
@@ -162,6 +164,7 @@ test('Propagates trace for outgoing fetch requests', async ({ baseURL }) => {
             'http.response.status_code': 200,
             'sentry.op': 'http.server',
             'sentry.origin': 'auto.http.otel.http',
+            'sentry.source': 'route',
           },
           op: 'http.server',
           span_id: expect.any(String),
@@ -186,6 +189,7 @@ test('Propagates trace for outgoing fetch requests', async ({ baseURL }) => {
             'http.response.status_code': 200,
             'sentry.op': 'http.server',
             'sentry.origin': 'auto.http.otel.http',
+            'sentry.source': 'route',
           },
           op: 'http.server',
           parent_span_id: outgoingHttpSpanId,
diff --git a/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/transactions.test.ts b/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/transactions.test.ts
index d2ab9e3d664f..0429adca8623 100644
--- a/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/transactions.test.ts
+++ b/dev-packages/e2e-tests/test-applications/node-experimental-fastify-app/tests/transactions.test.ts
@@ -30,6 +30,7 @@ test('Sends an API route transaction', async ({ baseURL }) => {
             'http.response.status_code': 200,
             'sentry.op': 'http.server',
             'sentry.origin': 'auto.http.otel.http',
+            'sentry.source': 'route',
           },
           op: 'http.server',
           span_id: expect.any(String),
diff --git a/dev-packages/node-integration-tests/suites/express/multiple-routers/complex-router/server.ts b/dev-packages/node-integration-tests/suites/express/multiple-routers/complex-router/server.ts
index 8df1b9c3d988..08b3a8f024cc 100644
--- a/dev-packages/node-integration-tests/suites/express/multiple-routers/complex-router/server.ts
+++ b/dev-packages/node-integration-tests/suites/express/multiple-routers/complex-router/server.ts
@@ -1,6 +1,5 @@
 import { loggingTransport, startExpressServerAndSendPortToRunner } from '@sentry-internal/node-integration-tests';
 import * as Sentry from '@sentry/node';
-import * as Tracing from '@sentry/tracing';
 import express from 'express';
 
 const app = express();
@@ -9,7 +8,7 @@ Sentry.init({
   dsn: 'https://public@dsn.ingest.sentry.io/1337',
   release: '1.0',
   // eslint-disable-next-line deprecation/deprecation
-  integrations: [new Sentry.Integrations.Http({ tracing: true }), new Tracing.Integrations.Express({ app })],
+  integrations: [new Sentry.Integrations.Http({ tracing: true }), new Sentry.Integrations.Express({ app })],
   tracesSampleRate: 1.0,
   transport: loggingTransport,
 });
diff --git a/packages/core/src/tracing/dynamicSamplingContext.ts b/packages/core/src/tracing/dynamicSamplingContext.ts
index ff4599a42a68..222763a8a781 100644
--- a/packages/core/src/tracing/dynamicSamplingContext.ts
+++ b/packages/core/src/tracing/dynamicSamplingContext.ts
@@ -3,6 +3,7 @@ import { dropUndefinedKeys } from '@sentry/utils';
 
 import { DEFAULT_ENVIRONMENT } from '../constants';
 import { getClient } from '../currentScopes';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '../semanticAttributes';
 import { getRootSpan } from '../utils/getRootSpan';
 import { spanIsSampled, spanToJSON } from '../utils/spanUtils';
 
@@ -66,7 +67,7 @@ export function getDynamicSamplingContextFromSpan(span: Span): Readonly<Partial<
   // TODO (v8): Replace txn.metadata with txn.attributes[]
   // We can't do this yet because attributes aren't always set yet.
   // eslint-disable-next-line deprecation/deprecation
-  const { sampleRate: maybeSampleRate, source } = txn.metadata;
+  const { sampleRate: maybeSampleRate } = txn.metadata;
   if (maybeSampleRate != null) {
     dsc.sample_rate = `${maybeSampleRate}`;
   }
@@ -74,6 +75,8 @@ export function getDynamicSamplingContextFromSpan(span: Span): Readonly<Partial<
   // We don't want to have a transaction name in the DSC if the source is "url" because URLs might contain PII
   const jsonSpan = spanToJSON(txn);
 
+  const source = (jsonSpan.data || {})[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
+
   // after JSON conversion, txn.name becomes jsonSpan.description
   if (source && source !== 'url') {
     dsc.transaction = jsonSpan.description;
diff --git a/packages/core/src/tracing/transaction.ts b/packages/core/src/tracing/transaction.ts
index cdea78e1880b..5c5b284f0d29 100644
--- a/packages/core/src/tracing/transaction.ts
+++ b/packages/core/src/tracing/transaction.ts
@@ -10,6 +10,7 @@ import type {
   TransactionContext,
   TransactionEvent,
   TransactionMetadata,
+  TransactionSource,
 } from '@sentry/types';
 import { dropUndefinedKeys, logger } from '@sentry/utils';
 
@@ -68,6 +69,11 @@ export class Transaction extends SentrySpan implements TransactionInterface {
 
     this._trimEnd = transactionContext.trimEnd;
 
+    this._attributes = {
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
+      ...this._attributes,
+    };
+
     // this is because transactions are also spans, and spans have a transaction pointer
     // TODO (v8): Replace this with another way to set the root span
     // eslint-disable-next-line deprecation/deprecation
@@ -110,17 +116,12 @@ export class Transaction extends SentrySpan implements TransactionInterface {
     // We merge attributes in for backwards compatibility
     return {
       // Defaults
-      // eslint-disable-next-line deprecation/deprecation
-      source: 'custom',
       spanMetadata: {},
 
       // Legacy metadata
       ...this._metadata,
 
       // From attributes
-      ...(this._attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE] && {
-        source: this._attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE] as TransactionMetadata['source'],
-      }),
       ...(this._attributes[SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE] && {
         sampleRate: this._attributes[SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE] as TransactionMetadata['sampleRate'],
       }),
@@ -142,7 +143,7 @@ export class Transaction extends SentrySpan implements TransactionInterface {
    *
    * @deprecated Use `.updateName()` and `.setAttribute()` instead.
    */
-  public setName(name: string, source: TransactionMetadata['source'] = 'custom'): void {
+  public setName(name: string, source: TransactionSource = 'custom'): void {
     this._name = name;
     this.setAttribute(SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, source);
   }
@@ -309,8 +310,8 @@ export class Transaction extends SentrySpan implements TransactionInterface {
 
     // eslint-disable-next-line deprecation/deprecation
     const { metadata } = this;
-    // eslint-disable-next-line deprecation/deprecation
-    const { source } = metadata;
+
+    const source = this._attributes['sentry.source'] as TransactionSource | undefined;
 
     const transaction: TransactionEvent = {
       contexts: {
diff --git a/packages/core/test/lib/tracing/dynamicSamplingContext.test.ts b/packages/core/test/lib/tracing/dynamicSamplingContext.test.ts
index 802769b3ec1f..9c531907eac3 100644
--- a/packages/core/test/lib/tracing/dynamicSamplingContext.test.ts
+++ b/packages/core/test/lib/tracing/dynamicSamplingContext.test.ts
@@ -75,7 +75,9 @@ describe('getDynamicSamplingContextFromSpan', () => {
       name: 'tx',
       metadata: {
         sampleRate: 0.56,
-        source: 'route',
+      },
+      attributes: {
+        [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
       },
       sampled: true,
     });
@@ -98,9 +100,11 @@ describe('getDynamicSamplingContextFromSpan', () => {
       const transaction = new Transaction({
         name: 'tx',
         metadata: {
-          source: 'url',
           sampleRate: 0.56,
         },
+        attributes: {
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
+        },
       });
 
       const dsc = getDynamicSamplingContextFromSpan(transaction);
@@ -110,11 +114,11 @@ describe('getDynamicSamplingContextFromSpan', () => {
     test.each([
       ['is included if transaction source is parameterized route/url', 'route'],
       ['is included if transaction source is a custom name', 'custom'],
-    ])('%s', (_: string, source) => {
+    ] as const)('%s', (_: string, source: TransactionSource) => {
       const transaction = startInactiveSpan({
         name: 'tx',
-        metadata: {
-          ...(source && { source: source as TransactionSource }),
+        attributes: {
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source,
         },
       });
 
diff --git a/packages/core/test/lib/tracing/trace.test.ts b/packages/core/test/lib/tracing/trace.test.ts
index d95f713147ec..1d06ea009937 100644
--- a/packages/core/test/lib/tracing/trace.test.ts
+++ b/packages/core/test/lib/tracing/trace.test.ts
@@ -266,6 +266,7 @@ describe('startSpan', () => {
         data: {
           'sentry.origin': 'auto.http.browser',
           'sentry.sample_rate': 0,
+          'sentry.source': 'custom',
         },
         origin: 'auto.http.browser',
         description: 'GET users/[id]',
diff --git a/packages/core/test/lib/tracing/transaction.test.ts b/packages/core/test/lib/tracing/transaction.test.ts
index 415c0448f78e..9371bda548fd 100644
--- a/packages/core/test/lib/tracing/transaction.test.ts
+++ b/packages/core/test/lib/tracing/transaction.test.ts
@@ -1,4 +1,9 @@
-import { SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE, SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, Transaction } from '../../../src';
+import {
+  SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE,
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
+  Transaction,
+} from '../../../src';
 
 describe('transaction', () => {
   describe('name', () => {
@@ -16,7 +21,7 @@ describe('transaction', () => {
       transaction.name = 'new name';
 
       expect(transaction.name).toEqual('new name');
-      expect(transaction.metadata.source).toEqual('custom');
+      expect(transaction.attributes['sentry.source']).toEqual('custom');
     });
 
     it('allows to update the name via setName', () => {
@@ -27,7 +32,7 @@ describe('transaction', () => {
       transaction.setName('new name');
 
       expect(transaction.name).toEqual('new name');
-      expect(transaction.metadata.source).toEqual('custom');
+      expect(transaction.attributes['sentry.source']).toEqual('custom');
     });
 
     it('allows to update the name via updateName', () => {
@@ -38,7 +43,7 @@ describe('transaction', () => {
       transaction.updateName('new name');
 
       expect(transaction.name).toEqual('new name');
-      expect(transaction.metadata.source).toEqual('route');
+      expect(transaction.attributes['sentry.source']).toEqual('route');
     });
     /* eslint-enable deprecation/deprecation */
   });
@@ -48,15 +53,13 @@ describe('transaction', () => {
     it('works with defaults', () => {
       const transaction = new Transaction({ name: 'span name' });
       expect(transaction.metadata).toEqual({
-        source: 'custom',
         spanMetadata: {},
       });
     });
 
     it('allows to set metadata in constructor', () => {
-      const transaction = new Transaction({ name: 'span name', metadata: { source: 'url', request: {} } });
+      const transaction = new Transaction({ name: 'span name', metadata: { request: {} } });
       expect(transaction.metadata).toEqual({
-        source: 'url',
         spanMetadata: {},
         request: {},
       });
@@ -71,37 +74,31 @@ describe('transaction', () => {
           [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 0.5,
         },
       });
+
       expect(transaction.metadata).toEqual({
-        source: 'url',
         sampleRate: 0.5,
         spanMetadata: {},
         request: {},
       });
-    });
-
-    it('allows to update metadata via setMetadata', () => {
-      const transaction = new Transaction({ name: 'span name', metadata: { source: 'url', request: {} } });
-
-      transaction.setMetadata({ source: 'route' });
 
-      expect(transaction.metadata).toEqual({
-        source: 'route',
-        spanMetadata: {},
-        request: {},
+      expect(transaction.attributes).toEqual({
+        [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'manual',
+        [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
+        [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 0.5,
       });
     });
 
-    it('allows to update metadata via setAttribute', () => {
-      const transaction = new Transaction({ name: 'span name', metadata: { source: 'url', request: {} } });
+    it('allows to update metadata via setMetadata', () => {
+      const transaction = new Transaction({ name: 'span name', metadata: {} });
 
-      transaction.setAttribute(SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, 'route');
+      transaction.setMetadata({ request: {} });
 
       expect(transaction.metadata).toEqual({
-        source: 'route',
         spanMetadata: {},
         request: {},
       });
     });
+
     /* eslint-enable deprecation/deprecation */
   });
 });
diff --git a/packages/deno/test/__snapshots__/mod.test.ts.snap b/packages/deno/test/__snapshots__/mod.test.ts.snap
index d728072d38d6..417acf1e7639 100644
--- a/packages/deno/test/__snapshots__/mod.test.ts.snap
+++ b/packages/deno/test/__snapshots__/mod.test.ts.snap
@@ -41,41 +41,6 @@ snapshot[`captureException 1`] = `
         },
         stacktrace: {
           frames: [
-            {
-              colno: 20,
-              filename: "ext:cli/40_testing.js",
-              function: "outerWrapped",
-              in_app: false,
-              lineno: 472,
-            },
-            {
-              colno: 33,
-              filename: "ext:cli/40_testing.js",
-              function: "exitSanitizer",
-              in_app: false,
-              lineno: 458,
-            },
-            {
-              colno: 31,
-              filename: "ext:cli/40_testing.js",
-              function: "resourceSanitizer",
-              in_app: false,
-              lineno: 410,
-            },
-            {
-              colno: 33,
-              filename: "ext:cli/40_testing.js",
-              function: "asyncOpSanitizer",
-              in_app: false,
-              lineno: 177,
-            },
-            {
-              colno: 11,
-              filename: "ext:cli/40_testing.js",
-              function: "innerWrapped",
-              in_app: false,
-              lineno: 526,
-            },
             {
               colno: 27,
               context_line: "  client.captureException(something());",
diff --git a/packages/deno/test/normalize.ts b/packages/deno/test/normalize.ts
index 64295932e00d..4dbbc8f3f6ec 100644
--- a/packages/deno/test/normalize.ts
+++ b/packages/deno/test/normalize.ts
@@ -152,9 +152,9 @@ function normalizeEvent(event: sentryTypes.Event): sentryTypes.Event {
   }
 
   if (event.exception?.values?.[0].stacktrace?.frames) {
-    // Exlcude Deno frames since these may change between versions
+    // Exclude Deno frames since these may change between versions
     event.exception.values[0].stacktrace.frames = event.exception.values[0].stacktrace.frames.filter(
-      frame => !frame.filename?.includes('deno:'),
+      frame => !frame.filename?.includes('deno:') && !frame.filename?.startsWith('ext:'),
     );
   }
 
diff --git a/packages/ember/addon/index.ts b/packages/ember/addon/index.ts
index f403df54284e..5f5cbf054666 100644
--- a/packages/ember/addon/index.ts
+++ b/packages/ember/addon/index.ts
@@ -9,6 +9,7 @@ import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, applySdkMetadata } from '@sentry/core
 import { GLOBAL_OBJ } from '@sentry/utils';
 import Ember from 'ember';
 
+import type { TransactionSource } from '@sentry/types';
 import type { EmberSentryConfig, GlobalConfig, OwnConfig } from './types';
 
 function _getSentryInitConfig(): EmberSentryConfig['sentry'] {
@@ -68,11 +69,12 @@ export const instrumentRoutePerformance = <T extends RouteConstructor>(BaseRoute
     description: string,
     fn: X,
     args: Parameters<X>,
+    source: TransactionSource,
   ): Promise<ReturnType<X>> => {
     return startSpan(
       {
         attributes: {
-          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'ember',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source,
         },
         op,
         name: description,
@@ -94,15 +96,22 @@ export const instrumentRoutePerformance = <T extends RouteConstructor>(BaseRoute
           this.fullRouteName,
           super.beforeModel.bind(this),
           args,
+          'custom',
         );
       }
 
       public async model(...args: unknown[]): Promise<unknown> {
-        return instrumentFunction('ui.ember.route.model', this.fullRouteName, super.model.bind(this), args);
+        return instrumentFunction('ui.ember.route.model', this.fullRouteName, super.model.bind(this), args, 'custom');
       }
 
       public afterModel(...args: unknown[]): void | Promise<unknown> {
-        return instrumentFunction('ui.ember.route.after_model', this.fullRouteName, super.afterModel.bind(this), args);
+        return instrumentFunction(
+          'ui.ember.route.after_model',
+          this.fullRouteName,
+          super.afterModel.bind(this),
+          args,
+          'custom',
+        );
       }
 
       public setupController(...args: unknown[]): void | Promise<unknown> {
@@ -111,6 +120,7 @@ export const instrumentRoutePerformance = <T extends RouteConstructor>(BaseRoute
           this.fullRouteName,
           super.setupController.bind(this),
           args,
+          'custom',
         );
       }
     },
diff --git a/packages/nextjs/src/common/withServerActionInstrumentation.ts b/packages/nextjs/src/common/withServerActionInstrumentation.ts
index 1f4cdaf992c9..0c54a4f5b665 100644
--- a/packages/nextjs/src/common/withServerActionInstrumentation.ts
+++ b/packages/nextjs/src/common/withServerActionInstrumentation.ts
@@ -1,4 +1,4 @@
-import { getIsolationScope } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, getIsolationScope } from '@sentry/core';
 import {
   addTracingExtensions,
   captureException,
@@ -94,8 +94,8 @@ async function withServerActionInstrumentationImplementation<A extends (...args:
             {
               op: 'function.server_action',
               name: `serverAction/${serverActionName}`,
-              metadata: {
-                source: 'route',
+              attributes: {
+                [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
               },
             },
             async span => {
diff --git a/packages/node-experimental/test/integration/scope.test.ts b/packages/node-experimental/test/integration/scope.test.ts
index 8f73f5487b2b..3f6c8a441216 100644
--- a/packages/node-experimental/test/integration/scope.test.ts
+++ b/packages/node-experimental/test/integration/scope.test.ts
@@ -88,7 +88,7 @@ describe('Integration | Scope', () => {
           expect.objectContaining({
             contexts: expect.objectContaining({
               trace: {
-                data: { 'otel.kind': 'INTERNAL', 'sentry.origin': 'manual' },
+                data: { 'otel.kind': 'INTERNAL', 'sentry.origin': 'manual', 'sentry.source': 'custom' },
                 span_id: spanId,
                 status: 'ok',
                 trace_id: traceId,
diff --git a/packages/node-experimental/test/integration/transactions.test.ts b/packages/node-experimental/test/integration/transactions.test.ts
index 72dd4966bc41..f1b89e922641 100644
--- a/packages/node-experimental/test/integration/transactions.test.ts
+++ b/packages/node-experimental/test/integration/transactions.test.ts
@@ -29,7 +29,9 @@ describe('Integration | Transactions', () => {
       {
         op: 'test op',
         name: 'test name',
-        source: 'task',
+        attributes: {
+          [Sentry.SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'task',
+        },
         origin: 'auto.test',
         metadata: { requestPath: 'test-path' },
       },
@@ -85,6 +87,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
@@ -106,7 +109,6 @@ describe('Integration | Transactions', () => {
             transaction: 'test name',
           }),
           sampleRate: 1,
-          source: 'task',
           spanMetadata: expect.any(Object),
           requestPath: 'test-path',
         }),
@@ -185,26 +187,34 @@ describe('Integration | Transactions', () => {
     Sentry.addBreadcrumb({ message: 'test breadcrumb 1', timestamp: 123456 });
 
     Sentry.withIsolationScope(() => {
-      Sentry.startSpan({ op: 'test op', name: 'test name', source: 'task', origin: 'auto.test' }, span => {
-        Sentry.addBreadcrumb({ message: 'test breadcrumb 2', timestamp: 123456 });
+      Sentry.startSpan(
+        {
+          op: 'test op',
+          name: 'test name',
+          origin: 'auto.test',
+          attributes: { [Sentry.SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'task' },
+        },
+        span => {
+          Sentry.addBreadcrumb({ message: 'test breadcrumb 2', timestamp: 123456 });
 
-        span.setAttributes({
-          'test.outer': 'test value',
-        });
+          span.setAttributes({
+            'test.outer': 'test value',
+          });
 
-        const subSpan = Sentry.startInactiveSpan({ name: 'inner span 1' });
-        subSpan.end();
+          const subSpan = Sentry.startInactiveSpan({ name: 'inner span 1' });
+          subSpan.end();
 
-        Sentry.setTag('test.tag', 'test value');
+          Sentry.setTag('test.tag', 'test value');
 
-        Sentry.startSpan({ name: 'inner span 2' }, innerSpan => {
-          Sentry.addBreadcrumb({ message: 'test breadcrumb 3', timestamp: 123456 });
+          Sentry.startSpan({ name: 'inner span 2' }, innerSpan => {
+            Sentry.addBreadcrumb({ message: 'test breadcrumb 3', timestamp: 123456 });
 
-          innerSpan.setAttributes({
-            'test.inner': 'test value',
+            innerSpan.setAttributes({
+              'test.inner': 'test value',
+            });
           });
-        });
-      });
+        },
+      );
     });
 
     Sentry.withIsolationScope(() => {
@@ -251,6 +261,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
@@ -297,6 +308,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op b',
               'sentry.origin': 'manual',
+              'sentry.source': 'custom',
             },
             op: 'test op b',
             span_id: expect.any(String),
@@ -409,6 +421,7 @@ describe('Integration | Transactions', () => {
             data: {
               'otel.kind': 'INTERNAL',
               'sentry.origin': 'manual',
+              'sentry.source': 'custom',
             },
             span_id: expect.any(String),
             status: 'ok',
@@ -452,6 +465,7 @@ describe('Integration | Transactions', () => {
             data: {
               'otel.kind': 'INTERNAL',
               'sentry.origin': 'manual',
+              'sentry.source': 'custom',
             },
             span_id: expect.any(String),
             status: 'ok',
@@ -508,12 +522,20 @@ describe('Integration | Transactions', () => {
     context.with(
       trace.setSpanContext(setPropagationContextOnContext(context.active(), propagationContext), spanContext),
       () => {
-        Sentry.startSpan({ op: 'test op', name: 'test name', source: 'task', origin: 'auto.test' }, () => {
-          const subSpan = Sentry.startInactiveSpan({ name: 'inner span 1' });
-          subSpan.end();
+        Sentry.startSpan(
+          {
+            op: 'test op',
+            name: 'test name',
+            origin: 'auto.test',
+            attributes: { [Sentry.SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'task' },
+          },
+          () => {
+            const subSpan = Sentry.startInactiveSpan({ name: 'inner span 1' });
+            subSpan.end();
 
-          Sentry.startSpan({ name: 'inner span 2' }, () => {});
-        });
+            Sentry.startSpan({ name: 'inner span 2' }, () => {});
+          },
+        );
       },
     );
 
@@ -531,6 +553,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
diff --git a/packages/node/src/handlers.ts b/packages/node/src/handlers.ts
index 0ac97daae7c7..8e1cb695c05b 100644
--- a/packages/node/src/handlers.ts
+++ b/packages/node/src/handlers.ts
@@ -72,7 +72,7 @@ export function tracingHandler(): (
           op: 'http.server',
           origin: 'auto.http.node.tracingHandler',
           ...ctx,
-          data: {
+          attributes: {
             [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source,
           },
           metadata: {
diff --git a/packages/node/test/integrations/http.test.ts b/packages/node/test/integrations/http.test.ts
index 2af325d5ddbd..af550ef70643 100644
--- a/packages/node/test/integrations/http.test.ts
+++ b/packages/node/test/integrations/http.test.ts
@@ -1,6 +1,7 @@
 import * as http from 'http';
 import * as https from 'https';
 import type { SentrySpan } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import { Transaction } from '@sentry/core';
 import { getCurrentScope, makeMain, setUser, spanToJSON, startInactiveSpan } from '@sentry/core';
 import { Hub, addTracingExtensions } from '@sentry/core';
@@ -162,7 +163,7 @@ describe('tracing', () => {
   it('adds the transaction name to the the baggage header if a valid transaction source is set', async () => {
     nock('http://dogs.are.great').get('/').reply(200);
 
-    createTransactionOnScope({}, { metadata: { source: 'route' } });
+    createTransactionOnScope({}, { attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route' } });
 
     const request = http.get({ host: 'http://dogs.are.great/', headers: { baggage: 'dog=great' } });
     const baggageHeader = request.getHeader('baggage') as string;
@@ -176,7 +177,7 @@ describe('tracing', () => {
   it('does not add the transaction name to the the baggage header if url transaction source is set', async () => {
     nock('http://dogs.are.great').get('/').reply(200);
 
-    createTransactionOnScope({}, { metadata: { source: 'url' } });
+    createTransactionOnScope({}, { attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url' } });
 
     const request = http.get({ host: 'http://dogs.are.great/', headers: { baggage: 'dog=great' } });
     const baggageHeader = request.getHeader('baggage') as string;
diff --git a/packages/opentelemetry-node/src/spanprocessor.ts b/packages/opentelemetry-node/src/spanprocessor.ts
index 9996fc73111f..f79dc9f5b2e4 100644
--- a/packages/opentelemetry-node/src/spanprocessor.ts
+++ b/packages/opentelemetry-node/src/spanprocessor.ts
@@ -179,7 +179,9 @@ function getTraceData(otelSpan: OtelSpan, parentContext: Context): Partial<Trans
     metadata: {
       // only set dynamic sampling context if sentry-trace header was set
       dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
-      source: 'custom',
+    },
+    attributes: {
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
     },
   };
 
diff --git a/packages/opentelemetry-node/test/spanprocessor.test.ts b/packages/opentelemetry-node/test/spanprocessor.test.ts
index c5e54b8d642d..b5e2a26fa4c2 100644
--- a/packages/opentelemetry-node/test/spanprocessor.test.ts
+++ b/packages/opentelemetry-node/test/spanprocessor.test.ts
@@ -5,6 +5,7 @@ import type { Span as OtelSpan } from '@opentelemetry/sdk-trace-base';
 import { NodeTracerProvider } from '@opentelemetry/sdk-trace-node';
 import { SemanticAttributes, SemanticResourceAttributes } from '@opentelemetry/semantic-conventions';
 import type { SpanStatusType } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import { captureException, getCurrentScope, setCurrentClient } from '@sentry/core';
 import { SentrySpan, Transaction, addTracingExtensions, createTransport, spanToJSON } from '@sentry/core';
 import { NodeClient } from '@sentry/node';
@@ -671,7 +672,7 @@ describe('SentrySpanProcessor', () => {
         otelSpan.end();
 
         // eslint-disable-next-line deprecation/deprecation
-        expect(sentrySpan?.transaction?.metadata.source).toBe('url');
+        expect(sentrySpan?.transaction?.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('url');
       });
     });
 
@@ -687,7 +688,7 @@ describe('SentrySpanProcessor', () => {
         otelSpan.end();
 
         // eslint-disable-next-line deprecation/deprecation
-        expect(sentrySpan?.transaction?.metadata.source).toBe('route');
+        expect(sentrySpan?.transaction?.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('route');
       });
     });
 
@@ -703,7 +704,7 @@ describe('SentrySpanProcessor', () => {
         otelSpan.end();
 
         // eslint-disable-next-line deprecation/deprecation
-        expect(sentrySpan?.transaction?.metadata.source).toBe('route');
+        expect(sentrySpan?.transaction?.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('route');
       });
     });
 
diff --git a/packages/opentelemetry/src/spanExporter.ts b/packages/opentelemetry/src/spanExporter.ts
index 1f6792932dcd..e8baeb17d2cc 100644
--- a/packages/opentelemetry/src/spanExporter.ts
+++ b/packages/opentelemetry/src/spanExporter.ts
@@ -4,6 +4,7 @@ import { ExportResultCode } from '@opentelemetry/core';
 import type { ReadableSpan, SpanExporter } from '@opentelemetry/sdk-trace-base';
 import { SemanticAttributes } from '@opentelemetry/semantic-conventions';
 import type { Transaction } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import { SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE, flush, getCurrentHub } from '@sentry/core';
 import type { Scope, Span as SentrySpan, SpanOrigin, TransactionSource } from '@sentry/types';
 import { addNonEnumerableProperty, logger } from '@sentry/utils';
@@ -159,10 +160,12 @@ function createTransactionForOtelSpan(span: ReadableSpan): Transaction {
     status: mapStatus(span),
     startTimestamp: convertOtelTimeToSeconds(span.startTime),
     metadata: {
-      source,
       sampleRate: span.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE] as number | undefined,
       ...metadata,
     },
+    attributes: {
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source,
+    },
     data: removeSentryAttributes(data),
     origin,
     tags,
diff --git a/packages/opentelemetry/test/custom/transaction.test.ts b/packages/opentelemetry/test/custom/transaction.test.ts
index ae07939981cc..f56350abeb8e 100644
--- a/packages/opentelemetry/test/custom/transaction.test.ts
+++ b/packages/opentelemetry/test/custom/transaction.test.ts
@@ -24,7 +24,6 @@ describe('startTranscation', () => {
     expect(transaction.spanRecorder?.spans).toHaveLength(1);
     // eslint-disable-next-line deprecation/deprecation
     expect(transaction.metadata).toEqual({
-      source: 'custom',
       spanMetadata: {},
     });
 
@@ -55,7 +54,6 @@ describe('startTranscation', () => {
     expect(transaction).toBeInstanceOf(Transaction);
     // eslint-disable-next-line deprecation/deprecation
     expect(transaction.metadata).toEqual({
-      source: 'custom',
       spanMetadata: {},
     });
 
diff --git a/packages/opentelemetry/test/integration/scope.test.ts b/packages/opentelemetry/test/integration/scope.test.ts
index cc4def42ddbc..594fa1bcf9ae 100644
--- a/packages/opentelemetry/test/integration/scope.test.ts
+++ b/packages/opentelemetry/test/integration/scope.test.ts
@@ -98,6 +98,7 @@ describe('Integration | Scope', () => {
                 data: {
                   'otel.kind': 'INTERNAL',
                   'sentry.origin': 'manual',
+                  'sentry.source': 'custom',
                 },
                 span_id: spanId,
                 status: 'ok',
diff --git a/packages/opentelemetry/test/integration/transactions.test.ts b/packages/opentelemetry/test/integration/transactions.test.ts
index 2da60af0195d..08a62e93361d 100644
--- a/packages/opentelemetry/test/integration/transactions.test.ts
+++ b/packages/opentelemetry/test/integration/transactions.test.ts
@@ -1,6 +1,6 @@
 import { TraceFlags, context, trace } from '@opentelemetry/api';
 import type { SpanProcessor } from '@opentelemetry/sdk-trace-base';
-import { addBreadcrumb, getClient, setTag, withIsolationScope } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, addBreadcrumb, getClient, setTag, withIsolationScope } from '@sentry/core';
 import type { PropagationContext, TransactionEvent } from '@sentry/types';
 import { logger } from '@sentry/utils';
 
@@ -31,9 +31,11 @@ describe('Integration | Transactions', () => {
       {
         op: 'test op',
         name: 'test name',
-        source: 'task',
         origin: 'auto.test',
         metadata: { requestPath: 'test-path' },
+        attributes: {
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'task',
+        },
       },
       span => {
         addBreadcrumb({ message: 'test breadcrumb 2', timestamp: 123456 });
@@ -86,6 +88,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
@@ -106,7 +109,6 @@ describe('Integration | Transactions', () => {
             transaction: 'test name',
           }),
           sampleRate: 1,
-          source: 'task',
           spanMetadata: expect.any(Object),
           requestPath: 'test-path',
         }),
@@ -250,6 +252,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
@@ -296,6 +299,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op b',
               'sentry.origin': 'manual',
+              'sentry.source': 'custom',
             },
             op: 'test op b',
             span_id: expect.any(String),
@@ -377,6 +381,7 @@ describe('Integration | Transactions', () => {
               'otel.kind': 'INTERNAL',
               'sentry.op': 'test op',
               'sentry.origin': 'auto.test',
+              'sentry.source': 'task',
             },
             op: 'test op',
             span_id: expect.any(String),
diff --git a/packages/opentelemetry/test/trace.test.ts b/packages/opentelemetry/test/trace.test.ts
index 5785eb7fdb00..fa6e1d09dad8 100644
--- a/packages/opentelemetry/test/trace.test.ts
+++ b/packages/opentelemetry/test/trace.test.ts
@@ -218,8 +218,10 @@ describe('trace', () => {
           name: 'outer',
           op: 'my-op',
           origin: 'auto.test.origin',
-          source: 'task',
           metadata: { requestPath: 'test-path' },
+          attributes: {
+            [InternalSentrySemanticAttributes.SOURCE]: 'task',
+          },
         },
         span => {
           expect(span).toBeDefined();
@@ -335,7 +337,9 @@ describe('trace', () => {
         name: 'outer',
         op: 'my-op',
         origin: 'auto.test.origin',
-        source: 'task',
+        attributes: {
+          [InternalSentrySemanticAttributes.SOURCE]: 'task',
+        },
         metadata: { requestPath: 'test-path' },
       });
 
diff --git a/packages/remix/src/client/performance.tsx b/packages/remix/src/client/performance.tsx
index 10e91837149d..347e8a2f73e8 100644
--- a/packages/remix/src/client/performance.tsx
+++ b/packages/remix/src/client/performance.tsx
@@ -78,8 +78,8 @@ export function startPageloadSpan(): void {
     op: 'pageload',
     origin: 'auto.pageload.remix',
     tags: DEFAULT_TAGS,
-    metadata: {
-      source: 'url',
+    attributes: {
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
     },
   };
 
@@ -103,8 +103,8 @@ function startNavigationSpan(matches: RouteMatch<string>[]): void {
     op: 'navigation',
     origin: 'auto.navigation.remix',
     tags: DEFAULT_TAGS,
-    metadata: {
-      source: 'route',
+    attributes: {
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
     },
   };
 
diff --git a/packages/remix/src/utils/instrumentServer.ts b/packages/remix/src/utils/instrumentServer.ts
index 19e541fd4ebc..7eb30e46af12 100644
--- a/packages/remix/src/utils/instrumentServer.ts
+++ b/packages/remix/src/utils/instrumentServer.ts
@@ -1,6 +1,7 @@
 /* eslint-disable max-lines */
 import {
   SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
   getActiveSpan,
   getActiveTransaction,
   getClient,
@@ -415,13 +416,13 @@ export function startRequestHandlerTransaction(
     op: 'http.server',
     attributes: {
       [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.http.remix',
+      [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source,
     },
     tags: {
       method: request.method,
     },
     ...traceparentData,
     metadata: {
-      source,
       dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
     },
   });
diff --git a/packages/sveltekit/src/client/load.ts b/packages/sveltekit/src/client/load.ts
index 3e454bdb364a..621015badbf1 100644
--- a/packages/sveltekit/src/client/load.ts
+++ b/packages/sveltekit/src/client/load.ts
@@ -1,4 +1,9 @@
-import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN, handleCallbackErrors, startSpan } from '@sentry/core';
+import {
+  SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
+  handleCallbackErrors,
+  startSpan,
+} from '@sentry/core';
 import { captureException } from '@sentry/svelte';
 import { addNonEnumerableProperty, objectify } from '@sentry/utils';
 import type { LoadEvent } from '@sveltejs/kit';
@@ -86,12 +91,10 @@ export function wrapLoadWithSentry<T extends (...args: any) => any>(origLoad: T)
           op: 'function.sveltekit.load',
           attributes: {
             [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+            [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: routeId ? 'route' : 'url',
           },
           name: routeId ? routeId : event.url.pathname,
           status: 'ok',
-          metadata: {
-            source: routeId ? 'route' : 'url',
-          },
         },
         () => handleCallbackErrors(() => wrappingTarget.apply(thisArg, [patchedEvent]), sendErrorToSentry),
       );
diff --git a/packages/sveltekit/src/server/handle.ts b/packages/sveltekit/src/server/handle.ts
index e06838cca413..cc53f7541923 100644
--- a/packages/sveltekit/src/server/handle.ts
+++ b/packages/sveltekit/src/server/handle.ts
@@ -1,5 +1,6 @@
 import {
   SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
   getActiveSpan,
   getCurrentScope,
   getDynamicSamplingContextFromSpan,
@@ -179,12 +180,12 @@ async function instrumentHandle(
         op: 'http.server',
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.http.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: event.route?.id ? 'route' : 'url',
         },
         name: `${event.request.method} ${event.route?.id || event.url.pathname}`,
         status: 'ok',
         ...traceparentData,
         metadata: {
-          source: event.route?.id ? 'route' : 'url',
           dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
         },
       },
diff --git a/packages/sveltekit/src/server/load.ts b/packages/sveltekit/src/server/load.ts
index 9728dcf47b5b..0d73b27a9d1b 100644
--- a/packages/sveltekit/src/server/load.ts
+++ b/packages/sveltekit/src/server/load.ts
@@ -1,5 +1,10 @@
 /* eslint-disable @sentry-internal/sdk/no-optional-chaining */
-import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN, getCurrentScope, startSpan } from '@sentry/core';
+import {
+  SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
+  getCurrentScope,
+  startSpan,
+} from '@sentry/core';
 import { captureException } from '@sentry/node';
 import { addNonEnumerableProperty, objectify } from '@sentry/utils';
 import type { LoadEvent, ServerLoadEvent } from '@sveltejs/kit';
@@ -69,12 +74,10 @@ export function wrapLoadWithSentry<T extends (...args: any) => any>(origLoad: T)
         op: 'function.sveltekit.load',
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: routeId ? 'route' : 'url',
         },
         name: routeId ? routeId : event.url.pathname,
         status: 'ok',
-        metadata: {
-          source: routeId ? 'route' : 'url',
-        },
       };
 
       try {
@@ -138,11 +141,11 @@ export function wrapServerLoadWithSentry<T extends (...args: any) => any>(origSe
         op: 'function.sveltekit.server.load',
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: routeId ? 'route' : 'url',
         },
         name: routeId ? routeId : event.url.pathname,
         status: 'ok',
         metadata: {
-          source: routeId ? 'route' : 'url',
           dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
         },
         data: {
diff --git a/packages/sveltekit/test/client/load.test.ts b/packages/sveltekit/test/client/load.test.ts
index ca7c1d625224..3c625865cf1c 100644
--- a/packages/sveltekit/test/client/load.test.ts
+++ b/packages/sveltekit/test/client/load.test.ts
@@ -3,7 +3,7 @@ import type { Load } from '@sveltejs/kit';
 import { redirect } from '@sveltejs/kit';
 import { vi } from 'vitest';
 
-import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN, SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import { wrapLoadWithSentry } from '../../src/client/load';
 
 const mockCaptureException = vi.spyOn(SentrySvelte, 'captureException').mockImplementation(() => 'xx');
@@ -109,13 +109,11 @@ describe('wrapLoadWithSentry', () => {
         {
           attributes: {
             [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+            [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
           },
           op: 'function.sveltekit.load',
           name: '/users/[id]',
           status: 'ok',
-          metadata: {
-            source: 'route',
-          },
         },
         expect.any(Function),
       );
@@ -139,13 +137,11 @@ describe('wrapLoadWithSentry', () => {
         {
           attributes: {
             [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+            [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
           },
           op: 'function.sveltekit.load',
           name: '/users/123',
           status: 'ok',
-          metadata: {
-            source: 'url',
-          },
         },
         expect.any(Function),
       );
diff --git a/packages/sveltekit/test/server/handle.test.ts b/packages/sveltekit/test/server/handle.test.ts
index 9bba3c99e68e..019eab5992d0 100644
--- a/packages/sveltekit/test/server/handle.test.ts
+++ b/packages/sveltekit/test/server/handle.test.ts
@@ -1,4 +1,4 @@
-import { addTracingExtensions } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, addTracingExtensions } from '@sentry/core';
 import { NodeClient, setCurrentClient } from '@sentry/node';
 import * as SentryNode from '@sentry/node';
 import type { Transaction } from '@sentry/types';
@@ -133,7 +133,7 @@ describe('handleSentry', () => {
       expect(ref.name).toEqual('GET /users/[id]');
       expect(ref.op).toEqual('http.server');
       expect(ref.status).toEqual(isError ? 'internal_error' : 'ok');
-      expect(ref.metadata.source).toEqual('route');
+      expect(ref.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('route');
 
       expect(ref.endTimestamp).toBeDefined();
       expect(ref.spanRecorder.spans).toHaveLength(1);
@@ -169,7 +169,7 @@ describe('handleSentry', () => {
       expect(ref.name).toEqual('GET /users/[id]');
       expect(ref.op).toEqual('http.server');
       expect(ref.status).toEqual(isError ? 'internal_error' : 'ok');
-      expect(ref.metadata.source).toEqual('route');
+      expect(ref.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('route');
 
       expect(ref.endTimestamp).toBeDefined();
 
diff --git a/packages/sveltekit/test/server/load.test.ts b/packages/sveltekit/test/server/load.test.ts
index 388541a8d884..790ded799106 100644
--- a/packages/sveltekit/test/server/load.test.ts
+++ b/packages/sveltekit/test/server/load.test.ts
@@ -1,4 +1,4 @@
-import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN, addTracingExtensions } from '@sentry/core';
+import { SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN, SEMANTIC_ATTRIBUTE_SENTRY_SOURCE, addTracingExtensions } from '@sentry/core';
 import * as SentryNode from '@sentry/node';
 import type { Load, ServerLoad } from '@sveltejs/kit';
 import { error, redirect } from '@sveltejs/kit';
@@ -199,13 +199,11 @@ describe('wrapLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
         },
         op: 'function.sveltekit.load',
         name: '/users/[id]',
         status: 'ok',
-        metadata: {
-          source: 'route',
-        },
       },
       expect.any(Function),
     );
@@ -220,13 +218,11 @@ describe('wrapLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
         },
         op: 'function.sveltekit.load',
         name: '/users/123',
         status: 'ok',
-        metadata: {
-          source: 'url',
-        },
       },
       expect.any(Function),
     );
@@ -256,6 +252,7 @@ describe('wrapServerLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
         },
         op: 'function.sveltekit.server.load',
         name: '/users/[id]',
@@ -275,7 +272,6 @@ describe('wrapServerLoadWithSentry calls trace', () => {
             trace_id: '1234567890abcdef1234567890abcdef',
             transaction: 'dogpark',
           },
-          source: 'route',
         },
       },
       expect.any(Function),
@@ -291,16 +287,15 @@ describe('wrapServerLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
         },
         op: 'function.sveltekit.server.load',
         name: '/users/[id]',
         status: 'ok',
+        metadata: {},
         data: {
           'http.method': 'GET',
         },
-        metadata: {
-          source: 'route',
-        },
       },
       expect.any(Function),
     );
@@ -315,6 +310,7 @@ describe('wrapServerLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
         },
         op: 'function.sveltekit.server.load',
         name: '/users/[id]',
@@ -327,7 +323,6 @@ describe('wrapServerLoadWithSentry calls trace', () => {
         },
         metadata: {
           dynamicSamplingContext: {},
-          source: 'route',
         },
       },
       expect.any(Function),
@@ -346,6 +341,7 @@ describe('wrapServerLoadWithSentry calls trace', () => {
       {
         attributes: {
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.sveltekit',
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
         },
         op: 'function.sveltekit.server.load',
         name: '/users/123',
@@ -365,7 +361,6 @@ describe('wrapServerLoadWithSentry calls trace', () => {
             trace_id: '1234567890abcdef1234567890abcdef',
             transaction: 'dogpark',
           },
-          source: 'url',
         },
       },
       expect.any(Function),
diff --git a/packages/tracing-internal/src/browser/browserTracingIntegration.ts b/packages/tracing-internal/src/browser/browserTracingIntegration.ts
index 95dee0c42f5e..ad70af5aa666 100644
--- a/packages/tracing-internal/src/browser/browserTracingIntegration.ts
+++ b/packages/tracing-internal/src/browser/browserTracingIntegration.ts
@@ -236,16 +236,15 @@ export const browserTracingIntegration = ((_options: Partial<BrowserTracingOptio
     const finalContext = beforeStartSpan ? beforeStartSpan(expandedContext) : expandedContext;
 
     // If `beforeStartSpan` set a custom name, record that fact
-    // eslint-disable-next-line deprecation/deprecation
-    finalContext.metadata =
+    finalContext.attributes =
       finalContext.name !== expandedContext.name
-        ? // eslint-disable-next-line deprecation/deprecation
-          { ...finalContext.metadata, source: 'custom' }
-        : // eslint-disable-next-line deprecation/deprecation
-          finalContext.metadata;
+        ? { ...finalContext.attributes, [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom' }
+        : finalContext.attributes;
 
     latestRouteName = finalContext.name;
-    latestRouteSource = getSource(finalContext);
+    if (finalContext.attributes) {
+      latestRouteSource = finalContext.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
+    }
 
     if (finalContext.sampled === false) {
       DEBUG_BUILD && logger.log(`[Tracing] Will not send ${finalContext.op} transaction because of beforeNavigate.`);
@@ -480,13 +479,3 @@ function registerInteractionListener(
     addEventListener(type, registerInteractionTransaction, { once: false, capture: true });
   });
 }
-
-function getSource(context: TransactionContext): TransactionSource | undefined {
-  const sourceFromAttributes = context.attributes && context.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
-  // eslint-disable-next-line deprecation/deprecation
-  const sourceFromData = context.data && context.data[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
-  // eslint-disable-next-line deprecation/deprecation
-  const sourceFromMetadata = context.metadata && context.metadata.source;
-
-  return sourceFromAttributes || sourceFromData || sourceFromMetadata;
-}
diff --git a/packages/tracing-internal/src/browser/browsertracing.ts b/packages/tracing-internal/src/browser/browsertracing.ts
index 393cd7c69016..2aceb97bd6a1 100644
--- a/packages/tracing-internal/src/browser/browsertracing.ts
+++ b/packages/tracing-internal/src/browser/browsertracing.ts
@@ -330,16 +330,15 @@ export class BrowserTracing implements Integration {
     const finalContext = modifiedContext === undefined ? { ...expandedContext, sampled: false } : modifiedContext;
 
     // If `beforeNavigate` set a custom name, record that fact
-    // eslint-disable-next-line deprecation/deprecation
-    finalContext.metadata =
+    finalContext.attributes =
       finalContext.name !== expandedContext.name
-        ? // eslint-disable-next-line deprecation/deprecation
-          { ...finalContext.metadata, source: 'custom' }
-        : // eslint-disable-next-line deprecation/deprecation
-          finalContext.metadata;
+        ? { ...finalContext.attributes, [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom' }
+        : finalContext.attributes;
 
     this._latestRouteName = finalContext.name;
-    this._latestRouteSource = getSource(finalContext);
+    if (finalContext.attributes) {
+      this._latestRouteSource = finalContext.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
+    }
 
     // eslint-disable-next-line deprecation/deprecation
     if (finalContext.sampled === false) {
@@ -452,13 +451,3 @@ export function getMetaContent(metaName: string): string | undefined {
   // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
   return metaTag ? metaTag.getAttribute('content') : undefined;
 }
-
-function getSource(context: TransactionContext): TransactionSource | undefined {
-  const sourceFromAttributes = context.attributes && context.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
-  // eslint-disable-next-line deprecation/deprecation
-  const sourceFromData = context.data && context.data[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE];
-  // eslint-disable-next-line deprecation/deprecation
-  const sourceFromMetadata = context.metadata && context.metadata.source;
-
-  return sourceFromAttributes || sourceFromData || sourceFromMetadata;
-}
diff --git a/packages/tracing-internal/src/browser/router.ts b/packages/tracing-internal/src/browser/router.ts
index 27ad22ad90cc..895a37c60ff1 100644
--- a/packages/tracing-internal/src/browser/router.ts
+++ b/packages/tracing-internal/src/browser/router.ts
@@ -1,3 +1,4 @@
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import type { Transaction, TransactionContext } from '@sentry/types';
 import { addHistoryInstrumentationHandler, browserPerformanceTimeOrigin, logger } from '@sentry/utils';
 
@@ -27,7 +28,9 @@ export function instrumentRoutingWithDefaults<T extends Transaction>(
       startTimestamp: browserPerformanceTimeOrigin ? browserPerformanceTimeOrigin / 1000 : undefined,
       op: 'pageload',
       origin: 'auto.pageload.browser',
-      metadata: { source: 'url' },
+      attributes: {
+        [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
+      },
     });
   }
 
@@ -58,7 +61,9 @@ export function instrumentRoutingWithDefaults<T extends Transaction>(
           name: WINDOW.location.pathname,
           op: 'navigation',
           origin: 'auto.navigation.browser',
-          metadata: { source: 'url' },
+          attributes: {
+            [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
+          },
         });
       }
     });
diff --git a/packages/tracing-internal/src/node/integrations/express.ts b/packages/tracing-internal/src/node/integrations/express.ts
index 7dabd973252e..617a7d981cf4 100644
--- a/packages/tracing-internal/src/node/integrations/express.ts
+++ b/packages/tracing-internal/src/node/integrations/express.ts
@@ -376,7 +376,7 @@ function instrumentRouter(appOrRouter: ExpressRouter): void {
 
       const transaction = res.__sentry_transaction;
       const attributes = (transaction && spanToJSON(transaction).data) || {};
-      if (transaction && attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE] !== 'custom') {
+      if (transaction && attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE] === 'url') {
         // If the request URL is '/' or empty, the reconstructed route will be empty.
         // Therefore, we fall back to setting the final route to '/' in this case.
         const finalRoute = req._reconstructedRoute || '/';
diff --git a/packages/tracing-internal/test/browser/browserTracingIntegration.test.ts b/packages/tracing-internal/test/browser/browserTracingIntegration.test.ts
index 7171d41592bd..2655ae05dbe7 100644
--- a/packages/tracing-internal/test/browser/browserTracingIntegration.test.ts
+++ b/packages/tracing-internal/test/browser/browserTracingIntegration.test.ts
@@ -233,6 +233,7 @@ describe('browserTracingIntegration', () => {
           [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'pageload',
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'manual',
           [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
         },
         span_id: expect.any(String),
         start_timestamp: expect.any(Number),
@@ -266,6 +267,7 @@ describe('browserTracingIntegration', () => {
           [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'pageload',
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.test',
           [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
           testy: 'yes',
         },
         span_id: expect.any(String),
@@ -327,6 +329,7 @@ describe('browserTracingIntegration', () => {
           [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'navigation',
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'manual',
           [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
         },
         span_id: expect.any(String),
         start_timestamp: expect.any(Number),
@@ -360,6 +363,7 @@ describe('browserTracingIntegration', () => {
           [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'navigation',
           [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.test',
           [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
+          [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
           testy: 'yes',
         },
         span_id: expect.any(String),
diff --git a/packages/tracing-internal/test/browser/browsertracing.test.ts b/packages/tracing-internal/test/browser/browsertracing.test.ts
index be16c8cf092e..fb93661607aa 100644
--- a/packages/tracing-internal/test/browser/browsertracing.test.ts
+++ b/packages/tracing-internal/test/browser/browsertracing.test.ts
@@ -1,5 +1,12 @@
 /* eslint-disable deprecation/deprecation */
-import { TRACING_DEFAULTS, getClient, getCurrentHub, setCurrentClient, spanToJSON } from '@sentry/core';
+import {
+  SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
+  TRACING_DEFAULTS,
+  getClient,
+  getCurrentHub,
+  setCurrentClient,
+  spanToJSON,
+} from '@sentry/core';
 import * as hubExtensions from '@sentry/core';
 import type { BaseTransportOptions, ClientOptions, DsnComponents, HandlerDataHistory } from '@sentry/types';
 import { JSDOM } from 'jsdom';
@@ -240,7 +247,7 @@ describe('BrowserTracing', () => {
         const transaction = getActiveTransaction() as IdleTransaction;
         expect(transaction).toBeDefined();
         expect(transaction.name).toBe('newName');
-        expect(transaction.metadata.source).toBe('custom');
+        expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('custom');
 
         expect(mockBeforeNavigation).toHaveBeenCalledTimes(1);
       });
@@ -252,13 +259,17 @@ describe('BrowserTracing', () => {
         createBrowserTracing(true, {
           beforeNavigate: mockBeforeNavigation,
           routingInstrumentation: (customStartTransaction: (obj: any) => void) => {
-            customStartTransaction({ name: 'a/path', op: 'pageload', metadata: { source: 'url' } });
+            customStartTransaction({
+              name: 'a/path',
+              op: 'pageload',
+              attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url' },
+            });
           },
         });
         const transaction = getActiveTransaction() as IdleTransaction;
         expect(transaction).toBeDefined();
         expect(transaction.name).toBe('a/path');
-        expect(transaction.metadata.source).toBe('url');
+        expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('url');
 
         expect(mockBeforeNavigation).toHaveBeenCalledTimes(1);
       });
diff --git a/packages/tracing-internal/test/browser/router.test.ts b/packages/tracing-internal/test/browser/router.test.ts
index a27926ad9803..e7a12ea91506 100644
--- a/packages/tracing-internal/test/browser/router.test.ts
+++ b/packages/tracing-internal/test/browser/router.test.ts
@@ -1,3 +1,4 @@
+import { SEMANTIC_ATTRIBUTE_SENTRY_SOURCE } from '@sentry/core';
 import type { HandlerDataHistory } from '@sentry/types';
 import { JSDOM } from 'jsdom';
 
@@ -45,7 +46,7 @@ conditionalTest({ min: 16 })('instrumentRoutingWithDefaults', () => {
       name: 'blank',
       op: 'pageload',
       origin: 'auto.pageload.browser',
-      metadata: { source: 'url' },
+      attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url' },
       startTimestamp: expect.any(Number),
     });
   });
@@ -80,7 +81,7 @@ conditionalTest({ min: 16 })('instrumentRoutingWithDefaults', () => {
         name: 'blank',
         op: 'navigation',
         origin: 'auto.navigation.browser',
-        metadata: { source: 'url' },
+        attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url' },
       });
     });
 
diff --git a/packages/tracing/test/span.test.ts b/packages/tracing/test/span.test.ts
index 8975b3762a64..f65ceb75eaf6 100644
--- a/packages/tracing/test/span.test.ts
+++ b/packages/tracing/test/span.test.ts
@@ -12,7 +12,7 @@ import {
   setCurrentClient,
   spanToJSON,
 } from '@sentry/core';
-import type { BaseTransportOptions, ClientOptions, TransactionSource } from '@sentry/types';
+import type { BaseTransportOptions, ClientOptions } from '@sentry/types';
 
 import { TRACEPARENT_REGEXP, Transaction } from '../src';
 import { getDefaultBrowserClientOptions } from './testutils';
@@ -667,8 +667,8 @@ describe('SentrySpan', () => {
         const transaction = new Transaction(
           {
             name: 'tx',
-            metadata: {
-              source: 'url',
+            attributes: {
+              [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'url',
             },
           },
           getCurrentHub(),
@@ -681,12 +681,12 @@ describe('SentrySpan', () => {
       test.each([
         ['is included if transaction source is paremeterized route/url', 'route'],
         ['is included if transaction source is a custom name', 'custom'],
-      ])('%s', (_: string, source) => {
+      ] as const)('%s', (_, source) => {
         const transaction = new Transaction(
           {
             name: 'tx',
-            metadata: {
-              ...(source && { source: source as TransactionSource }),
+            attributes: {
+              ...(source && { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: source }),
             },
           },
           getCurrentHub(),
diff --git a/packages/tracing/test/transaction.test.ts b/packages/tracing/test/transaction.test.ts
index f9e950dd9cb9..55d162becc21 100644
--- a/packages/tracing/test/transaction.test.ts
+++ b/packages/tracing/test/transaction.test.ts
@@ -16,17 +16,20 @@ describe('`Transaction` class', () => {
 
   describe('transaction name source', () => {
     it('sets source in constructor if provided', () => {
-      const transaction = new Transaction({ name: 'dogpark', metadata: { source: 'route' } });
+      const transaction = new Transaction({
+        name: 'dogpark',
+        attributes: { [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route' },
+      });
 
       expect(transaction.name).toEqual('dogpark');
-      expect(transaction.metadata.source).toEqual('route');
+      expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('route');
     });
 
     it("sets source to be `'custom'` in constructor if not provided", () => {
       const transaction = new Transaction({ name: 'dogpark' });
 
       expect(transaction.name).toEqual('dogpark');
-      expect(transaction.metadata.source).toBe('custom');
+      expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toBe('custom');
     });
 
     it("sets source to `'custom'` when assigning to `name` property", () => {
@@ -34,7 +37,7 @@ describe('`Transaction` class', () => {
       transaction.name = 'ballpit';
 
       expect(transaction.name).toEqual('ballpit');
-      expect(transaction.metadata.source).toEqual('custom');
+      expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('custom');
     });
 
     it('sets instrumenter to be `sentry` in constructor if not provided', () => {
@@ -55,7 +58,7 @@ describe('`Transaction` class', () => {
         transaction.setName('ballpit');
 
         expect(transaction.name).toEqual('ballpit');
-        expect(transaction.metadata.source).toEqual('custom');
+        expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('custom');
       });
 
       it('uses given `source` value', () => {
@@ -63,7 +66,7 @@ describe('`Transaction` class', () => {
         transaction.setName('ballpit', 'route');
 
         expect(transaction.name).toEqual('ballpit');
-        expect(transaction.metadata.source).toEqual('route');
+        expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('route');
       });
     });
 
@@ -74,7 +77,7 @@ describe('`Transaction` class', () => {
         transaction.updateName('ballpit');
 
         expect(transaction.name).toEqual('ballpit');
-        expect(transaction.metadata.source).toEqual('route');
+        expect(transaction.attributes[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]).toEqual('route');
       });
     });
   });
@@ -170,6 +173,7 @@ describe('`Transaction` class', () => {
               data: {
                 [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
                 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'manual',
+                [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
               },
               span_id: transaction.spanId,
               trace_id: transaction.traceId,
@@ -201,6 +205,7 @@ describe('`Transaction` class', () => {
               data: {
                 [SEMANTIC_ATTRIBUTE_SENTRY_SAMPLE_RATE]: 1,
                 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'manual',
+                [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'custom',
               },
               span_id: transaction.spanId,
               trace_id: transaction.traceId,
diff --git a/packages/types/src/span.ts b/packages/types/src/span.ts
index 69704d497b8f..f9e29a188327 100644
--- a/packages/types/src/span.ts
+++ b/packages/types/src/span.ts
@@ -2,7 +2,7 @@ import type { TraceContext } from './context';
 import type { Instrumenter } from './instrumenter';
 import type { Primitive } from './misc';
 import type { HrTime } from './opentelemetry';
-import type { Transaction } from './transaction';
+import type { Transaction, TransactionSource } from './transaction';
 
 type SpanOriginType = 'manual' | 'auto';
 type SpanOriginCategory = string; // e.g. http, db, ui, ....
@@ -26,7 +26,7 @@ export type SpanAttributeValue =
 export type SpanAttributes = Partial<{
   'sentry.origin': string;
   'sentry.op': string;
-  'sentry.source': string;
+  'sentry.source': TransactionSource;
   'sentry.sample_rate': number;
 }> &
   Record<string, SpanAttributeValue | undefined>;
diff --git a/packages/types/src/transaction.ts b/packages/types/src/transaction.ts
index 49b92b2e218a..df22d28de7fc 100644
--- a/packages/types/src/transaction.ts
+++ b/packages/types/src/transaction.ts
@@ -109,7 +109,7 @@ export interface Transaction extends TransactionContext, Omit<Span, 'setName' |
    *
    * @deprecated Use `.updateName()` and `.setAttribute()` instead.
    */
-  setName(name: string, source?: TransactionMetadata['source']): void;
+  setName(name: string, source?: TransactionSource): void;
 
   /**
    * Set the context of a transaction event.
@@ -209,12 +209,6 @@ export interface TransactionMetadata {
   /** TODO: If we rm -rf `instrumentServer`, this can go, too */
   requestPath?: string;
 
-  /**
-   * Information on how a transaction name was generated.
-   * @deprecated Use `SEMANTIC_ATTRIBUTE_SENTRY_SOURCE` attribute instead.
-   */
-  source: TransactionSource;
-
   /**
    * Metadata for the transaction's spans, keyed by spanId.
    * @deprecated This will be removed in v8.
diff --git a/packages/utils/src/requestdata.ts b/packages/utils/src/requestdata.ts
index 7b8c61d27750..19c2cbd18f4e 100644
--- a/packages/utils/src/requestdata.ts
+++ b/packages/utils/src/requestdata.ts
@@ -73,14 +73,15 @@ export function addRequestDataToTransaction(
   _deps?: InjectedNodeDeps,
 ): void {
   if (!transaction) return;
+
+  // TODO(v8): SEMANTIC_ATTRIBUTE_SENTRY_SOURCE is in core, align this once we merge utils & core
   // eslint-disable-next-line deprecation/deprecation
-  if (!transaction.metadata.source || transaction.metadata.source === 'url') {
+  if (!transaction.attributes['sentry.source'] || transaction.attributes['sentry.source'] === 'url') {
     // Attempt to grab a parameterized route off of the request
     const [name, source] = extractPathForTransaction(req, { path: true, method: true });
     transaction.updateName(name);
-    // TODO: SEMANTIC_ATTRIBUTE_SENTRY_SOURCE is in core, align this once we merge utils & core
-    // eslint-disable-next-line deprecation/deprecation
-    transaction.setMetadata({ source });
+    // TODO(v8): SEMANTIC_ATTRIBUTE_SENTRY_SOURCE is in core, align this once we merge utils & core
+    transaction.setAttribute('sentry.source', source);
   }
   transaction.setAttribute('url', req.originalUrl || req.url);
   if (req.baseUrl) {