diff --git a/tests/flake.nix b/tests/flake.nix
index 34f39d35c..1e2244681 100644
--- a/tests/flake.nix
+++ b/tests/flake.nix
@@ -15,7 +15,7 @@
 {
   description = "Tests of Home Manager for Nix";
 
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
 
   outputs =
     { nixpkgs, ... }: