diff --git a/src/Illuminate/Collections/Enumerable.php b/src/Illuminate/Collections/Enumerable.php
index eb050dec772a..be621adde94a 100644
--- a/src/Illuminate/Collections/Enumerable.php
+++ b/src/Illuminate/Collections/Enumerable.php
@@ -805,7 +805,7 @@ public function random($number = null);
      * @template TReduceInitial
      * @template TReduceReturnType
      *
-     * @param  callable(TReduceInitial|TReduceReturnType, TValue): TReduceReturnType  $callback
+     * @param  callable(TReduceInitial|TReduceReturnType, TValue, TKey): TReduceReturnType  $callback
      * @param  TReduceInitial  $initial
      * @return TReduceReturnType
      */
diff --git a/src/Illuminate/Collections/Traits/EnumeratesValues.php b/src/Illuminate/Collections/Traits/EnumeratesValues.php
index bb18f45593c3..f76c7f06ab53 100644
--- a/src/Illuminate/Collections/Traits/EnumeratesValues.php
+++ b/src/Illuminate/Collections/Traits/EnumeratesValues.php
@@ -744,7 +744,7 @@ function ($carry, $pipe) {
      * @template TReduceInitial
      * @template TReduceReturnType
      *
-     * @param  callable(TReduceInitial|TReduceReturnType, TValue): TReduceReturnType  $callback
+     * @param  callable(TReduceInitial|TReduceReturnType, TValue, TKey): TReduceReturnType  $callback
      * @param  TReduceInitial  $initial
      * @return TReduceReturnType
      */
@@ -808,7 +808,7 @@ class_basename(static::class), gettype($result)
      * @template TReduceWithKeysInitial
      * @template TReduceWithKeysReturnType
      *
-     * @param  callable(TReduceWithKeysInitial|TReduceWithKeysReturnType, TValue): TReduceWithKeysReturnType  $callback
+     * @param  callable(TReduceWithKeysInitial|TReduceWithKeysReturnType, TValue, TKey): TReduceWithKeysReturnType  $callback
      * @param  TReduceWithKeysInitial  $initial
      * @return TReduceWithKeysReturnType
      */
diff --git a/types/Support/Collection.php b/types/Support/Collection.php
index 0c335a25bce5..d2630a60d2ad 100644
--- a/types/Support/Collection.php
+++ b/types/Support/Collection.php
@@ -544,6 +544,14 @@
         assertType('User', $user);
         assertType('int', $int);
 
+        return 1;
+    }, 0));
+assertType('int', $collection
+    ->reduce(function ($int, $user, $key) {
+        assertType('User', $user);
+        assertType('int', $int);
+        assertType('int', $key);
+
         return 1;
     }, 0));
 
@@ -559,6 +567,14 @@
         assertType('User', $user);
         assertType('int', $int);
 
+        return 1;
+    }, 0));
+assertType('int', $collection
+    ->reduceWithKeys(function ($int, $user, $key) {
+        assertType('User', $user);
+        assertType('int', $int);
+        assertType('int', $key);
+
         return 1;
     }, 0));