diff --git a/src/Illuminate/Collections/Collection.php b/src/Illuminate/Collections/Collection.php
index d6f79b5400f9..1ab7474f89a6 100644
--- a/src/Illuminate/Collections/Collection.php
+++ b/src/Illuminate/Collections/Collection.php
@@ -608,7 +608,7 @@ public function hasAny($key)
     /**
      * Concatenate values of a given key as a string.
      *
-     * @param  callable|string|null  $value
+     * @param  (callable(TValue, TKey): mixed)|string|null  $value
      * @param  string|null  $glue
      * @return string
      */
diff --git a/src/Illuminate/Collections/Enumerable.php b/src/Illuminate/Collections/Enumerable.php
index 36c47995a1d4..836d4225608b 100644
--- a/src/Illuminate/Collections/Enumerable.php
+++ b/src/Illuminate/Collections/Enumerable.php
@@ -555,7 +555,7 @@ public function hasAny($key);
     /**
      * Concatenate values of a given key as a string.
      *
-     * @param  callable|string  $value
+     * @param  (callable(TValue, TKey): mixed)|string  $value
      * @param  string|null  $glue
      * @return string
      */
diff --git a/src/Illuminate/Collections/LazyCollection.php b/src/Illuminate/Collections/LazyCollection.php
index a79cb31315b7..c8fc497bbd05 100644
--- a/src/Illuminate/Collections/LazyCollection.php
+++ b/src/Illuminate/Collections/LazyCollection.php
@@ -622,7 +622,7 @@ public function hasAny($key)
     /**
      * Concatenate values of a given key as a string.
      *
-     * @param  callable|string  $value
+     * @param  (callable(TValue, TKey): mixed)|string  $value
      * @param  string|null  $glue
      * @return string
      */
diff --git a/types/Support/Collection.php b/types/Support/Collection.php
index 8a0805ee3be4..30d13f3943d7 100644
--- a/types/Support/Collection.php
+++ b/types/Support/Collection.php
@@ -538,6 +538,13 @@ function ($collection, $count) {
 assertType('bool', $collection->has(0));
 assertType('bool', $collection->has([0, 1]));
 
+assertType('string', $collection->implode(function ($user, $index) {
+    assertType('User', $user);
+    assertType('int', $index);
+
+    return 'string';
+}));
+
 assertType('Illuminate\Support\Collection<int, User>', $collection->intersect([new User]));
 
 assertType('Illuminate\Support\Collection<int, User>', $collection->intersectByKeys([new User]));
diff --git a/types/Support/LazyCollection.php b/types/Support/LazyCollection.php
index 51694fdf4488..eabbc28984b5 100644
--- a/types/Support/LazyCollection.php
+++ b/types/Support/LazyCollection.php
@@ -416,6 +416,13 @@
 assertType('bool', $collection->has(0));
 assertType('bool', $collection->has([0, 1]));
 
+assertType('string', $collection->implode(function ($user, $index) {
+    assertType('User', $user);
+    assertType('int', $index);
+
+    return 'string';
+}));
+
 assertType('Illuminate\Support\LazyCollection<int, User>', $collection->intersect([new User]));
 
 assertType('Illuminate\Support\LazyCollection<int, User>', $collection->intersectByKeys([new User]));