diff --git a/nixos/modules/system/boot/systemd/oomd.nix b/nixos/modules/system/boot/systemd/oomd.nix
index 000b18c01609..edc25784367a 100644
--- a/nixos/modules/system/boot/systemd/oomd.nix
+++ b/nixos/modules/system/boot/systemd/oomd.nix
@@ -49,15 +49,15 @@ in {
 
     systemd.slices."-".sliceConfig = lib.mkIf cfg.enableRootSlice {
       ManagedOOMMemoryPressure = "kill";
-      ManagedOOMMemoryPressureLimit = "80%";
+      ManagedOOMMemoryPressureLimit = lib.mkDefault "80%";
     };
     systemd.slices."system".sliceConfig = lib.mkIf cfg.enableSystemSlice {
       ManagedOOMMemoryPressure = "kill";
-      ManagedOOMMemoryPressureLimit = "80%";
+      ManagedOOMMemoryPressureLimit = lib.mkDefault "80%";
     };
     systemd.slices."user-".sliceConfig = lib.mkIf cfg.enableUserSlices {
       ManagedOOMMemoryPressure = "kill";
-      ManagedOOMMemoryPressureLimit = "80%";
+      ManagedOOMMemoryPressureLimit = lib.mkDefault "80%";
     };
     systemd.user.units."slice" = lib.mkIf cfg.enableUserSlices {
       text = ''