diff --git a/src/apply.ts b/src/apply.ts
index c75f136..17b3761 100644
--- a/src/apply.ts
+++ b/src/apply.ts
@@ -1,5 +1,11 @@
 import { Operation, DraftType } from './interface';
-import type { Draft, Options, Patches, ApplyMutableOptions } from './interface';
+import type {
+  Draft,
+  Patches,
+  ApplyMutableOptions,
+  ApplyOptions,
+  ApplyResult,
+} from './interface';
 import { deepClone, get, getType, isDraft, unescapePath } from './utils';
 import { create } from './create';
 
@@ -24,16 +30,11 @@ import { create } from './create';
  * expect(state).toEqual(apply(baseState, patches));
  * ```
  */
-export function apply<T extends object, F extends boolean = false>(
-  state: T,
-  patches: Patches,
-  applyOptions?:
-    | Pick<
-        Options<boolean, F>,
-        Exclude<keyof Options<boolean, F>, 'enablePatches'>
-      >
-    | ApplyMutableOptions
-) {
+export function apply<
+  T extends object,
+  F extends boolean = false,
+  A extends ApplyOptions<F> = ApplyOptions<F>
+>(state: T, patches: Patches, applyOptions?: A): ApplyResult<T, F, A> {
   let i: number;
   for (i = patches.length - 1; i >= 0; i -= 1) {
     const { value, op, path } = patches[i];
@@ -127,17 +128,17 @@ export function apply<T extends object, F extends boolean = false>(
   };
   if ((applyOptions as ApplyMutableOptions)?.mutable) {
     mutate(state);
-    return;
+    return undefined as ApplyResult<T, F, A>;
   }
   if (isDraft(state)) {
     if (applyOptions !== undefined) {
       throw new Error(`Cannot apply patches with options to a draft.`);
     }
     mutate(state as Draft<T>);
-    return state;
+    return state as ApplyResult<T, F, A>;
   }
   return create<T, F>(state, mutate, {
     ...applyOptions,
     enablePatches: false,
-  });
+  }) as any;
 }
diff --git a/src/interface.ts b/src/interface.ts
index 646fc61..58b83ad 100644
--- a/src/interface.ts
+++ b/src/interface.ts
@@ -197,3 +197,16 @@ export type Draft<T> = T extends Primitive | AtomicObject
   : T extends object
   ? DraftedObject<T>
   : T;
+
+export type ApplyOptions<F extends boolean> =
+  | Pick<
+      Options<boolean, F>,
+      Exclude<keyof Options<boolean, F>, 'enablePatches'>
+    >
+  | ApplyMutableOptions;
+
+export type ApplyResult<
+  T extends object,
+  F extends boolean = false,
+  A extends ApplyOptions<F> = ApplyOptions<F>
+> = A extends { mutable: true } ? void : T;
diff --git a/test/apply.test.ts b/test/apply.test.ts
index 0fec6df..3d16aad 100644
--- a/test/apply.test.ts
+++ b/test/apply.test.ts
@@ -1305,16 +1305,6 @@ test('merge multiple patches', () => {
       enablePatches: true,
     }
   );
-  console.log(
-    JSON.stringify(
-      {
-        patches,
-        inversePatches,
-      },
-      null,
-      2
-    )
-  );
   const [state1, patches1, inversePatches1] = create(
     state,
     (draft) => {
@@ -1390,8 +1380,13 @@ test('base - mutate', () => {
       },
     ],
   });
+  const nextState = apply(baseState, patches);
+  expect(nextState).toEqual({ a: { c: 2 } });
+  expect(baseState).toEqual({ a: { c: 1 } });
+
   const result = apply(baseState, patches, {
     mutable: true,
   });
   expect(baseState).toEqual({ a: { c: 2 } });
+  expect(result).toBeUndefined();
 });