diff --git a/src/ps-web-apis.ts b/src/ps-web-apis.ts
index 755f62a..7266d7f 100644
--- a/src/ps-web-apis.ts
+++ b/src/ps-web-apis.ts
@@ -82,6 +82,7 @@ export type WaitingRoomQueue = WaitingRoomQueueDefault | "auth" | "checkout" | "
 export type Fetch = (input: RequestInfo, init?: FetchOptions) => Promise<Response>;
 export type GetRosettaEnvByKey = (key: string) => string | undefined;
 export type WaitForCapacity = (queue: WaitingRoomQueue) => Promise<void>;
+export type GetUserCredit = () => Promise<number>;
 export type RegisterIframeMessageListener = (eventtype: string, listener: (event: any, iframe: HTMLIFrameElement) => void) => void;
 
 export interface WhoamiV1 {
@@ -272,6 +273,10 @@ export interface WaitingRoomV1 {
     waitForCapacity: WaitForCapacity;
 }
 
+export interface WalletV1 {
+    getUserCredit: GetUserCredit;
+}
+
 export type ILayer = "privacy" | "reject";
 export type IApp = "offerpage" | "checkout" | "cancellation";
 export type ITenant = "welt" | "bild";