diff --git a/nixos/modules/services/display-managers/gdm.nix b/nixos/modules/services/display-managers/gdm.nix
index 8013fbde9031..dd043cbf272a 100644
--- a/nixos/modules/services/display-managers/gdm.nix
+++ b/nixos/modules/services/display-managers/gdm.nix
@@ -200,6 +200,8 @@ in
 
   config = lib.mkIf cfg.enable {
 
+    warnings = lib.optional config.services.pulseaudio.enable "Support for Pulseaudio + gdm will be removed in NixOS 26.11";
+
     services.xserver.displayManager.lightdm.enable = false;
 
     users.users = lib.mkMerge [