diff --git a/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php b/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
index f3b450cd6caaa..ec6a114608800 100644
--- a/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
+++ b/src/Symfony/Contracts/Service/ServiceSubscriberTrait.php
@@ -51,7 +51,7 @@ public static function getSubscribedServices(): array
             $attribute = $attribute->newInstance();
             $attribute->key ??= self::class.'::'.$method->name;
             $attribute->type ??= $returnType instanceof \ReflectionNamedType ? $returnType->getName() : (string) $returnType;
-            $attribute->nullable = $returnType->allowsNull();
+            $attribute->nullable = $attribute->nullable ?: $returnType->allowsNull();
 
             if ($attribute->attributes) {
                 $services[] = $attribute;
diff --git a/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php b/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
index ba370265bac85..6b9785e0b978f 100644
--- a/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
+++ b/src/Symfony/Contracts/Tests/Service/ServiceSubscriberTraitTest.php
@@ -27,7 +27,8 @@ public function testMethodsOnParentsAndChildrenAreIgnoredInGetSubscribedServices
     {
         $expected = [
             TestService::class.'::aService' => Service2::class,
-            TestService::class.'::nullableService' => '?'.Service2::class,
+            TestService::class.'::nullableInAttribute' => '?'.Service2::class,
+            TestService::class.'::nullableReturnType' => '?'.Service2::class,
             new SubscribedService(TestService::class.'::withAttribute', Service2::class, true, new Required()),
         ];
 
@@ -103,8 +104,18 @@ public function aService(): Service2
     {
     }
 
+    #[SubscribedService(nullable: true)]
+    public function nullableInAttribute(): Service2
+    {
+        if (!$this->container->has(__METHOD__)) {
+            throw new \LogicException();
+        }
+
+        return $this->container->get(__METHOD__);
+    }
+
     #[SubscribedService]
-    public function nullableService(): ?Service2
+    public function nullableReturnType(): ?Service2
     {
     }