diff --git a/.changeset/angry-pets-push.md b/.changeset/angry-pets-push.md
new file mode 100644
index 00000000..0aebfaec
--- /dev/null
+++ b/.changeset/angry-pets-push.md
@@ -0,0 +1,5 @@
+---
+'@formwerk/core': patch
+---
+
+fix: return Promise<void> instead of Promise<unknown>
diff --git a/packages/core/src/useForm/useFormActions.ts b/packages/core/src/useForm/useFormActions.ts
index 07359db8..1e32f821 100644
--- a/packages/core/src/useForm/useFormActions.ts
+++ b/packages/core/src/useForm/useFormActions.ts
@@ -51,8 +51,8 @@ export interface FormActions<TForm extends FormObject, TOutput extends FormObjec
    * ```
    */
   handleSubmit: (
-    onSuccess: (payload: ConsumableData<TOutput>, ctx: SubmitContext) => MaybeAsync<unknown>,
-  ) => (e?: Event) => Promise<unknown>;
+    onSuccess: (payload: ConsumableData<TOutput>, ctx: SubmitContext) => MaybeAsync<void>,
+  ) => (e?: Event) => Promise<void>;
   /**
    * Resets the form to its initial state.
    */