diff --git a/src/Illuminate/Support/Testing/Fakes/NotificationFake.php b/src/Illuminate/Support/Testing/Fakes/NotificationFake.php
index 15dc07738e45..b610932b62da 100644
--- a/src/Illuminate/Support/Testing/Fakes/NotificationFake.php
+++ b/src/Illuminate/Support/Testing/Fakes/NotificationFake.php
@@ -174,7 +174,9 @@ public function sendNow($notifiables, $notification)
         }
 
         foreach ($notifiables as $notifiable) {
-            $notification->id = Uuid::uuid4()->toString();
+            if (! $notification->id) {
+                $notification->id = Uuid::uuid4()->toString();
+            }
 
             $this->notifications[get_class($notifiable)][$notifiable->getKey()][get_class($notification)][] = [
                 'notification' => $notification,
diff --git a/tests/Support/SupportTestingNotificationFakeTest.php b/tests/Support/SupportTestingNotificationFakeTest.php
index 0f2a0c83af3d..8149981f759e 100644
--- a/tests/Support/SupportTestingNotificationFakeTest.php
+++ b/tests/Support/SupportTestingNotificationFakeTest.php
@@ -46,6 +46,26 @@ public function testAssertNotSentTo()
             $this->assertThat($e, new ExceptionMessage('The unexpected [Illuminate\Tests\Support\NotificationStub] notification was sent.'));
         }
     }
+
+    public function testResettingNotificationId()
+    {
+        $notification = new NotificationStub();
+
+        $this->fake->send($this->user, $notification);
+
+        $id = $notification->id;
+
+        $this->fake->send($this->user, $notification);
+
+        $this->assertSame($id, $notification->id);
+
+        $notification->id = null;
+
+        $this->fake->send($this->user, $notification);
+
+        $this->assertNotNull($notification->id);
+        $this->assertNotSame($id, $notification->id);
+    }
 }
 
 class NotificationStub extends Notification