diff --git a/packages/next/shared/lib/utils.ts b/packages/next/shared/lib/utils.ts
index 8bafaf018789..7f152924823a 100644
--- a/packages/next/shared/lib/utils.ts
+++ b/packages/next/shared/lib/utils.ts
@@ -267,7 +267,7 @@ export type NextApiResponse<T = any> = ServerResponse & {
 export type NextApiHandler<T = any> = (
   req: NextApiRequest,
   res: NextApiResponse<T>
-) => void | Promise<void>
+) => unknown | Promise<unknown>
 
 /**
  * Utils