diff --git a/src/Tags/MountUrl.php b/src/Tags/MountUrl.php
index c6b6e0741d..6de47dacc0 100644
--- a/src/Tags/MountUrl.php
+++ b/src/Tags/MountUrl.php
@@ -29,6 +29,14 @@ private function mount($handle)
             return;
         }
 
-        return $collection->url(Site::current()->handle());
+        $currentSite = Site::current();
+        $site = $this->params->has('site') ? Site::get($this->params->get('site')) : $currentSite;
+
+        // If the target site is on a different domain, return an absolute URL.
+        $isDifferentDomain = parse_url($site->absoluteUrl(), PHP_URL_HOST) !== parse_url($currentSite->absoluteUrl(), PHP_URL_HOST);
+
+        return $isDifferentDomain
+            ? $collection->absoluteUrl($site->handle())
+            : $collection->url($site->handle());
     }
 }
diff --git a/tests/Tags/MountUrlTagTest.php b/tests/Tags/MountUrlTagTest.php
index f862ec9c7b..556c01bf48 100644
--- a/tests/Tags/MountUrlTagTest.php
+++ b/tests/Tags/MountUrlTagTest.php
@@ -3,6 +3,7 @@
 namespace Tests\Tags;
 
 use Facades\Tests\Factories\EntryFactory;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Test;
 use Statamic\Facades\Antlers;
 use Statamic\Facades\Collection;
@@ -14,28 +15,65 @@ class MountUrlTagTest extends TestCase
 {
     use PreventSavingStacheItemsToDisk;
 
-    #[Test]
-    public function it_gets_collection_mount()
+    public function setUp(): void
     {
+        parent::setUp();
+
         $this->setSites([
-            'english' => ['url' => 'http://localhost/', 'locale' => 'en'],
-            'french' => ['url' => 'http://localhost/fr/', 'locale' => 'fr'],
+            'english' => ['url' => 'http://example.com/', 'locale' => 'en'],
+            'french' => ['url' => 'http://example.com/fr/', 'locale' => 'fr'],
+            'german' => ['url' => 'http://example.de/', 'locale' => 'de'],
         ]);
 
-        Collection::make('pages')->sites(['english', 'french'])->routes([
+        Collection::make('pages')->sites(['english', 'french', 'german'])->routes([
             'english' => 'pages/{slug}',
             'french' => 'le-pages/{slug}',
+            'german' => 'der-pages/{slug}',
         ])->save();
+
         $mountEn = EntryFactory::collection('pages')->slug('blog')->locale('english')->id('blog-en')->create();
         $mountFr = EntryFactory::collection('pages')->slug('le-blog')->locale('french')->origin('blog-en')->id('blog-fr')->create();
+        $mountDe = EntryFactory::collection('pages')->slug('der-blog')->locale('german')->origin('blog-en')->id('blog-de')->create();
+
         Collection::make('blog')->routes('{mount}/{slug}')->mount($mountEn->id())->save();
+    }
 
-        $this->assertParseEquals('/pages/blog', '{{ mount_url:blog }}');
-        $this->assertParseEquals('/pages/blog', '{{ mount_url handle="blog" }}');
+    #[Test]
+    #[DataProvider('mountProvider')]
+    public function it_gets_url($currentSite, $template, $expected)
+    {
+        Site::setCurrent($currentSite);
+        $this->assertParseEquals($expected, $template);
+    }
 
-        Site::setCurrent('french');
-        $this->assertParseEquals('/fr/le-pages/le-blog', '{{ mount_url:blog }}');
-        $this->assertParseEquals('/fr/le-pages/le-blog', '{{ mount_url handle="blog" }}');
+    public static function mountProvider()
+    {
+        return [
+            ['english', '{{ mount_url:blog }}', '/pages/blog'],
+            ['english', '{{ mount_url:blog site="english" }}', '/pages/blog'],
+            ['english', '{{ mount_url:blog site="french" }}', '/fr/le-pages/le-blog'],
+            ['english', '{{ mount_url:blog site="german" }}', 'http://example.de/der-pages/der-blog'],
+            ['french', '{{ mount_url:blog }}', '/fr/le-pages/le-blog'],
+            ['french', '{{ mount_url:blog site="english" }}', '/pages/blog'],
+            ['french', '{{ mount_url:blog site="french" }}', '/fr/le-pages/le-blog'],
+            ['french', '{{ mount_url:blog site="german" }}', 'http://example.de/der-pages/der-blog'],
+            ['german', '{{ mount_url:blog }}', '/der-pages/der-blog'],
+            ['german', '{{ mount_url:blog site="english" }}', 'http://example.com/pages/blog'],
+            ['german', '{{ mount_url:blog site="french" }}', 'http://example.com/fr/le-pages/le-blog'],
+            ['german', '{{ mount_url:blog site="german" }}', '/der-pages/der-blog'],
+            ['english', '{{ mount_url handle="blog" }}', '/pages/blog'],
+            ['english', '{{ mount_url handle="blog" site="english" }}', '/pages/blog'],
+            ['english', '{{ mount_url handle="blog" site="french" }}', '/fr/le-pages/le-blog'],
+            ['english', '{{ mount_url handle="blog" site="german" }}', 'http://example.de/der-pages/der-blog'],
+            ['french', '{{ mount_url handle="blog" }}', '/fr/le-pages/le-blog'],
+            ['french', '{{ mount_url handle="blog" site="english" }}', '/pages/blog'],
+            ['french', '{{ mount_url handle="blog" site="french" }}', '/fr/le-pages/le-blog'],
+            ['french', '{{ mount_url handle="blog" site="german" }}', 'http://example.de/der-pages/der-blog'],
+            ['german', '{{ mount_url handle="blog" }}', '/der-pages/der-blog'],
+            ['german', '{{ mount_url handle="blog" site="english" }}', 'http://example.com/pages/blog'],
+            ['german', '{{ mount_url handle="blog" site="french" }}', 'http://example.com/fr/le-pages/le-blog'],
+            ['german', '{{ mount_url handle="blog" site="german" }}', '/der-pages/der-blog'],
+        ];
     }
 
     private function assertParseEquals($expected, $template, $context = [])