diff --git a/nixos/modules/services/networking/bind.nix b/nixos/modules/services/networking/bind.nix
index 225e330ad184..6079062db6c3 100644
--- a/nixos/modules/services/networking/bind.nix
+++ b/nixos/modules/services/networking/bind.nix
@@ -45,7 +45,7 @@ let
         default = [ "any" ];
       };
       extraConfig = lib.mkOption {
-        type = lib.types.str;
+        type = lib.types.lines;
         description = "Extra zone config to be appended at the end of the zone section.";
         default = "";
       };