API Overview

Documentation Release Notes
- September 2026
  - Acceptance Devices | PAX All-in-One Android Solution Integration Guide
  - Acceptance Devices | Tap to Pay on Android Solution Integration Guide
  - Acceptance Devices | Tap to Pay on iPhone Solution Integration Guide
  - Digital Accept Secure Integration Developer Guide
  - Independent Software Vendors
  - OAuth 2.0 Partner Implementation Guide
  - Unified Checkout Developer Guide
  - Unified Click to Pay Developer Guide
- August 2026
  - Acceptance Devices | PAX All-in-One Android Solution Integration Guide
  - Acceptance Devices | Tap to Pay on Android Solution Integration Guide
  - Click to Pay Drop-In UI Developer Guide
  - Credentialed Transactions Developer Guide
  - Digital Accept Secure Integration Developer Guide
  - Invoicing Developer Guide
  - Merchant Boarding User Guide
  - Pay by Link Developer Guide
  - Payer Authentication Developer Guide
  - Simple Order API Field Reference
  - Unified Checkout Developer Guide
- July 2026
  - Acceptance Devices | PAX A77 Terminal User Guide
  - Acceptance Devices | PAX A920 MAX Terminal User Guide
  - Acceptance Devices | PAX A920 PRO Terminal User Guide
  - Acceptance Devices | PAX All-in-One Android Solution Integration Guide
  - Acceptance Devices | PAX IM30 Terminal User Guide
  - Acceptance Devices | Tap to Pay on Android Solution Integration Guide
  - BIN Lookup Service Developer Guide
  - Getting Started with REST Developer Guide
  - P12 Authentication Upgrade for SOAP Toolkit Key Users Migration Guide
  - Unified Checkout Developer Guide
  - Unified Click to Pay Developer Guide
- June 2026
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Acceptance Devices | Tap to Pay on iPhone Solution
  - Card Present Connect | Mass Transit
  - Getting Started with REST
  - Secure Acceptance to Unified Checkout
  - Simple Order API Field Reference
- May 2026
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Card Present Connect | Electric Vehicle Charging
  - Card Present Connect | Lodging
  - Click to Pay Drop-In UI
  - P12 Authentication Upgrade for SOAP Toolkit Key Users
  - Paze
  - Recurring Billing
- April 2026
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Solution
  - Getting Started with REST
  - OAuth
  - Payments
  - Simple Order API Field Reference
  - Unified Checkout
  - Unified Click to Pay
- March 2026
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Acceptance Devices | Tap to Pay on iPhone Solution
  - Healthcare Processing
  - Klarna Integration
  - Payer Authentication
  - Simple Order API Field Reference
  - Unified Checkout
  - Unified Click to Pay
- February 2026
  - Acceptance Devices | PAX A35 Terminal
  - Acceptance Devices | PAX A920 Terminal
  - Acceptance Devices | PAX A920 MAX Terminal
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | PAX IM30 Terminal
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Acceptance Devices | Tap to Pay on iPhone Solution
  - Card Present Connect | Electric Vehicle Charging
  - Card Present Connect | Mass Transit
  - Credentialed Transactions
  - Getting Started with REST
  - Invoicing
  - Pay by Link
  - REST API Field Reference
  - Unified Click to Pay
- January 2026
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Solution
  - Acceptance Devices | Tap to Pay on iPhone Solution
  - Card Present Connect | Retail
  - Payer Authentication
  - PIN Debit Processing
  - Secure Acceptance to Unified Checkout Migration
  - Simple Order API Field Reference
  - Visa Currency Conversion
- December 2025
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Card Present Connect | Mass Transit
  - Click to Pay Drop-In UI
  - Digital Accept Secure Integration
  - Getting Started with REST
  - Unified Checkout
- November 2025
  - Acceptance Devices | PAX A35 Terminal
  - Acceptance Devices | PAX A77 Terminal
  - Acceptance Devices | PAX A920 Terminal
  - Acceptance Devices | PAX A920 MAX Terminal
  - Acceptance Devices | PAX A920 PRO Terminal
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | PAX IM30 Terminal
  - Acceptance Devices | Tap to Pay on Android Solution
  - Digital Accept Secure Integration
  - Getting Started with REST
  - Invoicing
  - OAuth 2.0
  - Unified Checkout
- October 2025
  - Acceptance Devices | PAX Acceptance Devices App
  - Acceptance Devices | PAX All-in-One Android Solution
  - Acceptance Devices | Tap to Pay on Android Acceptance Devices App
  - Acceptance Devices | Tap to Pay on Android Solution
  - Click to Pay Drop-In UI
  - Digital Accept Secure Integration
  - Unified Checkout
  - Webhooks

On This Page

Invoicing Developer Guide

26.08.01

Added new section to update payment notification emails. See Update Payment Notification Email Address

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