diff --git a/types/async/index.d.ts b/types/async/index.d.ts
index 7c32079086..c94c8058c2 100644
--- a/types/async/index.d.ts
+++ b/types/async/index.d.ts
@@ -174,9 +174,9 @@ export function parallel<T, E>(tasks: Dictionary<AsyncFunction<T, E>>, callback?
 export function parallelLimit<T, E>(tasks: Array<AsyncFunction<T, E>>, limit: number, callback?: AsyncResultArrayCallback<T, E>): void;
 export function parallelLimit<T, E>(tasks: Dictionary<AsyncFunction<T, E>>, limit: number, callback?: AsyncResultObjectCallback<T, E>): void;
 export function whilst<E>(test: () => boolean, fn: AsyncVoidFunction<E>, callback: ErrorCallback<E>): void;
-export function doWhilst<E>(fn: AsyncVoidFunction<E>, test: (result?: any) => boolean, callback: ErrorCallback<E>): void;
+export function doWhilst<T, E>(fn: AsyncFunction<T, E>, test: (result?: any) => boolean, callback: ErrorCallback<E>): void;
 export function until<E>(test: () => boolean, fn: AsyncVoidFunction<E>, callback: ErrorCallback<E>): void;
-export function doUntil<E>(fn: AsyncVoidFunction<E>, test: (result?: any) => boolean, callback: ErrorCallback<E>): void;
+export function doUntil<T, E>(fn: AsyncFunction<T, E>, test: (result?: any) => boolean, callback: ErrorCallback<E>): void;
 export function during<E>(test: (testCallback : AsyncBooleanResultCallback<E>) => void, fn: AsyncVoidFunction<E>, callback: ErrorCallback<E>): void;
 export function doDuring<E>(fn: AsyncVoidFunction<E>, test: (testCallback: AsyncBooleanResultCallback<E>) => void, callback: ErrorCallback<E>): void;
 export function forever<E>(next: (next : ErrorCallback<E>) => void, errBack: ErrorCallback<E>) : void;