diff --git a/doc/release-notes/rl-2505.section.md b/doc/release-notes/rl-2505.section.md
index 2a44045fecb3..c71ac169d78b 100644
--- a/doc/release-notes/rl-2505.section.md
+++ b/doc/release-notes/rl-2505.section.md
@@ -76,6 +76,7 @@
     - `lib.types.attrsWith`
     - `lib.types.listOf`
     - `lib.types.unique` and `lib.types.uniq`
+    - `lib.types.nullOr`
 
 - Plasma 5 and Qt 5 based versions of associated software are deprecated in NixOS 25.05, and will be removed in NixOS 25.11. Users are encouraged to upgrade to Plasma 6.
 
diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index dbbb92d4400d..5bdc6e983501 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -413,14 +413,20 @@ NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribu
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.listOf.type.functor.wrapped ./deprecated-wrapped.nix
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedListOf.type.functor.wrapped ./deprecated-wrapped.nix
 
-NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.unique.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
-NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedUnique.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.listOf.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedListOf.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
 # unique / uniq
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.unique.type.functor.wrapped ./deprecated-wrapped.nix
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedUnique.type.functor.wrapped ./deprecated-wrapped.nix
 
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.unique.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
 NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedUnique.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
+# nullOr
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.nullOr.type.functor.wrapped ./deprecated-wrapped.nix
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedNullOr.type.functor.wrapped ./deprecated-wrapped.nix
+
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.nullOr.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
+NIX_ABORT_ON_WARN=1 checkConfigError 'The deprecated `.*functor.wrapped` attribute .*is accessed, use `.*nestedTypes.elemType` instead.' options.mergedNullOr.type.nestedTypes.elemType.functor.wrapped ./deprecated-wrapped.nix
 
 # Even with multiple assignments, a type error should be thrown if any of them aren't valid
 checkConfigError 'A definition for option .* is not of type .*' \
diff --git a/lib/tests/modules/deprecated-wrapped.nix b/lib/tests/modules/deprecated-wrapped.nix
index dc9771ec38c1..fcdfef7dea71 100644
--- a/lib/tests/modules/deprecated-wrapped.nix
+++ b/lib/tests/modules/deprecated-wrapped.nix
@@ -7,6 +7,7 @@ let
     attrsOf
     listOf
     unique
+    nullOr
     ;
 in
 {
@@ -34,6 +35,13 @@ in
         options.mergedUnique = mkOption {
           type = unique { message = ""; } (listOf types.str);
         };
+        # nullOr
+        options.nullOr = mkOption {
+          type = nullOr (listOf types.str);
+        };
+        options.mergedNullOr = mkOption {
+          type = nullOr (listOf types.str);
+        };
       }
     )
     # Module B
@@ -49,6 +57,9 @@ in
         options.mergedUnique = mkOption {
           type = unique { message = ""; } (listOf types.str);
         };
+        options.mergedNullOr = mkOption {
+          type = nullOr (listOf types.str);
+        };
       }
     )
   ];
diff --git a/lib/types.nix b/lib/types.nix
index 62aa337c167a..f38f96c33786 100644
--- a/lib/types.nix
+++ b/lib/types.nix
@@ -866,7 +866,9 @@ rec {
       getSubOptions = elemType.getSubOptions;
       getSubModules = elemType.getSubModules;
       substSubModules = m: nullOr (elemType.substSubModules m);
-      functor = (defaultFunctor name) // { wrapped = elemType; };
+      functor = (elemTypeFunctor name { inherit elemType; }) // {
+        type = payload: types.nullOr payload.elemType;
+      };
       nestedTypes.elemType = elemType;
     };