diff --git a/src/Illuminate/Http/Client/PendingRequest.php b/src/Illuminate/Http/Client/PendingRequest.php
index 71660e1c2298..ceb657736b5d 100644
--- a/src/Illuminate/Http/Client/PendingRequest.php
+++ b/src/Illuminate/Http/Client/PendingRequest.php
@@ -131,7 +131,7 @@ class PendingRequest
     /**
      * The number of milliseconds to wait between retries.
      *
-     * @var int
+     * @var Closure|int
      */
     protected $retryDelay = 100;
 
@@ -557,12 +557,12 @@ public function connectTimeout(int $seconds)
      * Specify the number of times the request should be attempted.
      *
      * @param  int  $times
-     * @param  int  $sleepMilliseconds
+     * @param  Closure|int  $sleepMilliseconds
      * @param  callable|null  $when
      * @param  bool  $throw
      * @return $this
      */
-    public function retry(int $times, int $sleepMilliseconds = 0, ?callable $when = null, bool $throw = true)
+    public function retry(int $times, Closure|int $sleepMilliseconds = 0, ?callable $when = null, bool $throw = true)
     {
         $this->tries = $times;
         $this->retryDelay = $sleepMilliseconds;
diff --git a/tests/Http/HttpClientTest.php b/tests/Http/HttpClientTest.php
index d0fd33198ab5..f15b0ae71d93 100644
--- a/tests/Http/HttpClientTest.php
+++ b/tests/Http/HttpClientTest.php
@@ -1576,6 +1576,31 @@ public function testExceptionThrownInRetryCallbackWithoutRetrying()
         $this->factory->assertSentCount(1);
     }
 
+    public function testRequestsWillBeWaitingSleepMillisecondsReceivedBeforeRetry()
+    {
+        $startTime = microtime(true);
+
+        $this->factory->fake([
+            '*' => $this->factory->sequence()
+                ->push(['error'], 500)
+                ->push(['error'], 500)
+                ->push(['ok'], 200),
+        ]);
+
+        $this->factory
+            ->retry(3, function ($attempt, $exception) {
+                $this->assertInstanceOf(RequestException::class, $exception);
+
+                return $attempt * 100;
+            }, null, true)
+            ->get('http://foo.com/get');
+
+        $this->factory->assertSentCount(3);
+
+        // Make sure was waited 300ms for the first two attempts
+        $this->assertEqualsWithDelta(0.3, microtime(true) - $startTime, 0.03);
+    }
+
     public function testMiddlewareRunsWhenFaked()
     {
         $this->factory->fake(function (Request $request) {