Cash App Pay

NEW (v5.3.0)

Table of contents

Cash App Pay is currently available in the following region(s): US

With our latest enhancements, you can now support taking Cash App Pay payments using your Afterpay merchant account. To do this, you must generate a token by sending a server-to-server call to the Afterpay API Create Checkout endpoint with a parameter of isCashAppPay set to true. This method requires importing and implementing the Cash App PayKit SDK.

When creating a checkout token, you must set both redirectConfirmUrl and redirectCancelUrl. If they are not set, an error will be returned from the server and the SDK will ouput a malformed JSON error. The SDK’s example merchant server sets the parameters here. See more details at Redirect Method in the Standard Checkout API.

Step 1: Install the Cash App Pay Kit SDK

Installation (Option One): SPM

You can install Pay Kit via SPM. Create a new Xcode project and navigate to File > Swift Packages > Add Package Dependency. Enter the URL and tap Next. Choose the main branch, and on the next screen, download the required packages.

Installation (Option Two): Cocoapods

Add Cocoapods to your project. Open the Podfile and add pod 'CashAppPayKit' and/or pod 'CashAppPayKitUI' and save your changes. Run pod update and Pay Kit will now be included through Cocoapods.

Step 2: Implement the Cash App Pay Observer Protocol

To receive updates from Pay Kit, you’ll need to implement the Cash App Pay Observer protocol. Your checkout view controller can conform to this protocol, or you can create a dedicated observer class.

The CashAppPayObserver protocol contains only one method:

func stateDidChange(to state: CashAppPaySDKState) {
	// handle state changes


Your implementation should switch on the state parameter and handle the appropriate state changes. Some of these possible states are for information only, but most drive the logic of your integration. The most critical states to handle are listed in the table below:

State Description
ReadyToAuthorize Show a Cash App Pay button in your UI and call authorizeCustomerRequest() when it is tapped.
Approved Grants are ready for your backend to use to create a payment.
Declined Customer has declined the Cash App Pay authorization and must start the flow over or choose a new payment method.

Error States

State Description
.integrationError A fixable bug in your integration.
.apiError A degradation of Cash App Pay server APIs. Your app should temporarily hide Cash App Pay functionality.
.unexpectedError A bug outside the normal flow. Report this bug (and what caused it) to Cash App Developer Support.

You must update your UI in response to these state changes.

Step 3: Implement URL handling

To use Pay Kit iOS, Cash App must be able to call a URL that will redirect back to your app. The simplest way to accomplish this is via Custom URL Schemes, but if your app supports Universal Links you may use those URLs as well.

Choose a unique scheme for your application and register it in Xcode from the Info tab of your application’s Target.

You’ll pass a URL that uses this scheme (or a Universal Link your app handles) into the createCustomerRequest() method that starts the authorization process.

When your app is called back by Cash App, simply post the CashAppPay.RedirectNotification from your AppDelegate or SceneDelegate, and the SDK will handle the rest:

import UIKit
import PayKit

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
  func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
    if let url = URLContexts.first?.url {
        name: CashAppPay.RedirectNotification,
        object: nil,
        userInfo: [UIApplication.LaunchOptionsKey.url : url]

Step 4: Instantiate Pay Kit iOS

When you’re ready to authorize a payment using Cash App Pay,

  1. Instantiate the SDK with the Afterpay Pay Kit Client ID via Afterpay.cashAppClientId.
  2. The SDK defaults to point to the production endpoint; for development, set the endpoint to .sandbox.
  3. Add your observer to the Pay Kit SDK.

Ensure that the Afterpay SDK is configured per the instructions before attempting to access Afterpay.cashAppClientId.

For example, from your checkout view controller that implements the PayKitObserver protocol, you might instantiate the SDK to be:

private let sandboxClientID = Afterpay.cashAppClientId
private lazy var sdk: CashAppPay = {
    let sdk = CashAppPay(clientID: sandboxClientID, endpoint: .sandbox)
    return sdk

Step 5: Create a Customer Request

You can create a customer request as soon as you know the amount you’d like to charge or if you’d like to create an on-file payment request. You must create this request as soon as your checkout view controller loads, so that your customer can authorize the request without delay.

Step 5A: Sign the Order Token

After retrieving the token from your server-to-server call, the order must be signed, so that you can retrieve the JWT and associated data. This might look like the following example:

let token = retrieveTokenFromServerToServerCall()
Afterpay.signCashAppOrderToken(token) { result in
  switch result {
  case .success(let cashData):
    // TODO: use `cashData` to create customer request (step 5B)
  case .failed(let reason):
    // TODO: handle failed signing either by retrying with a new Cash App
    // token or disabling / hiding the Cash App Pay button

Step 5B: Create a Pay Kit Customer Request

To charge a one-time payment, your Create Request call might look like this (in the following example, cashData is the response object that is returned in the didCommenceCheckout parameter from step 5A):

  params: CreateCustomerRequestParams(
    actions: [
        scopeID: cashData.brandId,
        money: Money(
          amount: cashData.amount,
          currency: .USD
    channel: .IN_APP,
    redirectURL: URL(string: cashData.redirectUri)!,
    referenceID: nil,
    metadata: nil

Your Observer’s state will change to .creatingCustomerRequest, then .readyToAuthorize with the created CustomerRequest struct as an associated value.

Step 6: Authorize the Customer Request

Step 6A: Add an Authorize Request Event to Cash App Pay button

Once the SDK is in the .readyToAuthorize state, you can store the associated CustomerRequest and display a Cash App Pay button. When the Customer taps the button, you can authorize the customer request. See CashAppPayButton to learn more about the Cash App Pay button component.


@objc func cashAppPayButtonTapped() {

Your app will redirect to Cash App for authorization. When the authorization is completed, your redirect URL will be called and the RedirectNotification will post. Then, the SDK will fetch your authorized request and return it to your Observer, as part of the change to the .approved state.

Step 6B: Validate the Cash App Pay Order

This step must not be skipped

Finally, you must validate the Cash App order. This will look like the following example:

Afterpay.validateCashAppOrder(jwt: cashData.jwt, customerId: customerId, grantId: { result in
  switch result {
  case .success(let data):
    // TODO: handle successful validation (ie pass grant and token to backend and then redirect to receipt page)
  case .failed(let reason):
    // TODO: handle invalid Cash App Order (ie start payment flow again)

Step 7: Pass Grants to the Backend and Capture Payment

The approved customer request will have grants associated with it which can be used with Afterpay’s Capture Payment API. Pass the grantId along with the token to capture using a server-to-server request.

Sequence Diagram

The below diagram describes the happy path.

  init: {
    'theme': 'base',
    'themeVariables': {
      'primaryColor': '#00c846',
      'primaryTextColor': '#FFFFFF',
      'primaryBorderColor': '#dfdfdf',
      'signalTextColor': '#000000',
      'signalColor': '#000000',
      'secondaryColor': '#006100',
      'tertiaryColor': '#fff'

  participant App
  participant Afterpay SDK
  participant Cash App Pay SDK
  participant Proxy Server

  participant Afterpay API
  Note over App,Afterpay API: Setup

  App->>Afterpay SDK: Configure the SDK
  Note over App,Afterpay SDK: Required for setting environment

  App->>Cash App Pay SDK: Create Cash App Pay instance
  Note over App,Cash App Pay SDK: Ensure same environment<br>as Afterpay SDK config

  App->>App: Implement<br>deep linking

  App->>Cash App Pay SDK: Register for state updates

  Note over App,Afterpay API: Create Customer Request and Capture

  App->>Proxy Server: Get Token Request

  Proxy Server->>Afterpay API: Create Checkout Request
  Note over Proxy Server,Afterpay API: Ensure same environment<br>as Afterpay SDK config<br><br>Request body should<br>contain `isCashAppPay: true`

  Afterpay API-->>Proxy Server: Create Checkout Response

  Note over Afterpay API,Proxy Server: Body contains a token

  Proxy Server-->>App: Get Token Response

  App->>Afterpay SDK: Sign the token

  Afterpay SDK->>Afterpay API: Token signing request

  Afterpay API-->>Afterpay SDK: Token signing response

  Afterpay SDK-->>App: Decoded token data

  App->>Cash App Pay SDK: Create a customer request

  App->>Cash App Pay SDK: Authorize the customer request

  App->>Afterpay SDK: Validate the order

  App->>Proxy Server: Upon approved state send capture request
  Note over App,Proxy Server: Pass the Grant Id (from the approved state)<br>and token in the body

  Proxy Server->>Afterpay API: Capture Payment Request

  Afterpay API-->>Proxy Server: Capture Payment Response

  Proxy Server-->>App: Capture Payment Respnse

  App->>App: Handle payment<br>capture response