diff --git a/packages/nextjs/src/common/wrapAppGetInitialPropsWithSentry.ts b/packages/nextjs/src/common/wrapAppGetInitialPropsWithSentry.ts
index 312e1b319fdb..7bd04342c0ab 100644
--- a/packages/nextjs/src/common/wrapAppGetInitialPropsWithSentry.ts
+++ b/packages/nextjs/src/common/wrapAppGetInitialPropsWithSentry.ts
@@ -56,10 +56,20 @@ export function wrapAppGetInitialPropsWithSentry(origAppGetInitialProps: AppGetI
         }
 
         if (requestSpan) {
-          appGetInitialProps.pageProps._sentryTraceData = spanToTraceHeader(requestSpan);
+          const sentryTrace = spanToTraceHeader(requestSpan);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (sentryTrace) {
+            appGetInitialProps.pageProps._sentryTraceData = sentryTrace;
+          }
+
           const dynamicSamplingContext = getDynamicSamplingContextFromSpan(requestSpan);
-          appGetInitialProps.pageProps._sentryBaggage =
-            dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+          const baggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (baggage) {
+            appGetInitialProps.pageProps._sentryBaggage = baggage;
+          }
         }
 
         return appGetInitialProps;
diff --git a/packages/nextjs/src/common/wrapErrorGetInitialPropsWithSentry.ts b/packages/nextjs/src/common/wrapErrorGetInitialPropsWithSentry.ts
index 71c8cf9806a5..347283494b38 100644
--- a/packages/nextjs/src/common/wrapErrorGetInitialPropsWithSentry.ts
+++ b/packages/nextjs/src/common/wrapErrorGetInitialPropsWithSentry.ts
@@ -49,10 +49,20 @@ export function wrapErrorGetInitialPropsWithSentry(
         const requestSpan = getSpanFromRequest(req) ?? (activeSpan ? getRootSpan(activeSpan) : undefined);
 
         if (requestSpan) {
-          errorGetInitialProps._sentryTraceData = spanToTraceHeader(requestSpan);
+          const sentryTrace = spanToTraceHeader(requestSpan);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (sentryTrace) {
+            errorGetInitialProps._sentryTraceData = sentryTrace;
+          }
 
           const dynamicSamplingContext = getDynamicSamplingContextFromSpan(requestSpan);
-          errorGetInitialProps._sentryBaggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+          const baggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (baggage) {
+            errorGetInitialProps._sentryBaggage = baggage;
+          }
         }
 
         return errorGetInitialProps;
diff --git a/packages/nextjs/src/common/wrapGetInitialPropsWithSentry.ts b/packages/nextjs/src/common/wrapGetInitialPropsWithSentry.ts
index 0b5425417913..1a1e351f83ed 100644
--- a/packages/nextjs/src/common/wrapGetInitialPropsWithSentry.ts
+++ b/packages/nextjs/src/common/wrapGetInitialPropsWithSentry.ts
@@ -45,10 +45,20 @@ export function wrapGetInitialPropsWithSentry(origGetInitialProps: GetInitialPro
         const requestSpan = getSpanFromRequest(req) ?? (activeSpan ? getRootSpan(activeSpan) : undefined);
 
         if (requestSpan) {
-          initialProps._sentryTraceData = spanToTraceHeader(requestSpan);
+          const sentryTrace = spanToTraceHeader(requestSpan);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (sentryTrace) {
+            initialProps._sentryTraceData = sentryTrace;
+          }
 
           const dynamicSamplingContext = getDynamicSamplingContextFromSpan(requestSpan);
-          initialProps._sentryBaggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+          const baggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (baggage) {
+            initialProps._sentryBaggage = baggage;
+          }
         }
 
         return initialProps;
diff --git a/packages/nextjs/src/common/wrapGetServerSidePropsWithSentry.ts b/packages/nextjs/src/common/wrapGetServerSidePropsWithSentry.ts
index d8a14b392462..1be908042b5e 100644
--- a/packages/nextjs/src/common/wrapGetServerSidePropsWithSentry.ts
+++ b/packages/nextjs/src/common/wrapGetServerSidePropsWithSentry.ts
@@ -38,13 +38,21 @@ export function wrapGetServerSidePropsWithSentry(
 
       if (serverSideProps && 'props' in serverSideProps) {
         const activeSpan = getActiveSpan();
-        const requestTransaction = getSpanFromRequest(req) ?? (activeSpan ? getRootSpan(activeSpan) : undefined);
-        if (requestTransaction) {
-          (serverSideProps.props as Record<string, unknown>)._sentryTraceData = spanToTraceHeader(requestTransaction);
-
-          const dynamicSamplingContext = getDynamicSamplingContextFromSpan(requestTransaction);
-          (serverSideProps.props as Record<string, unknown>)._sentryBaggage =
-            dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+        const requestSpan = getSpanFromRequest(req) ?? (activeSpan ? getRootSpan(activeSpan) : undefined);
+        if (requestSpan) {
+          const sentryTrace = spanToTraceHeader(requestSpan);
+
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (sentryTrace) {
+            (serverSideProps.props as Record<string, unknown>)._sentryTraceData = sentryTrace;
+          }
+
+          const dynamicSamplingContext = getDynamicSamplingContextFromSpan(requestSpan);
+          const baggage = dynamicSamplingContextToSentryBaggageHeader(dynamicSamplingContext);
+          // The Next.js serializer throws on undefined values so we need to guard for it (#12102)
+          if (baggage) {
+            (serverSideProps.props as Record<string, unknown>)._sentryBaggage = baggage;
+          }
         }
       }