diff --git a/authentik/providers/proxy/models.py b/authentik/providers/proxy/models.py
index 10237d218..9e3d0e78d 100644
--- a/authentik/providers/proxy/models.py
+++ b/authentik/providers/proxy/models.py
@@ -27,7 +27,7 @@ def get_cookie_secret():
 
 
 def _get_callback_url(uri: str) -> str:
-    return urljoin(uri, "/outpost.goauthentik.io/callback")
+    return urljoin(uri, "outpost.goauthentik.io/callback")
 
 
 class ProxyMode(models.TextChoices):