American Express Integration

This document details how to connect the American Express payment gateway to accept payments and how our integration works.


The American Express payment gateway on Invoiced supports the following features:

Capability Supported
Credit card payments
ACH payments
Vaulting cards
Vaulting bank accounts
Level 3 Processing
Apple Pay
ACH payment status


Connecting American Express is a straightforward process. Follow these steps to start accepting payments through American Express in minutes. These steps assume you already have a American Express account.

  1. From the Invoiced dashboard go to SettingsPayments.

  2. Click Setup on the payment method you want to accept.

  3. Click Connect Payment Gateway.

  4. Select American Express as the payment gateway.

  5. Enter in your American Express Merchant ID, API Password, and Domain. If you do not know your processing domain then you should leave it as the default.

  6. Click Save. Then click Enable and the payment method you selected should be enabled.

Client Workflow

Credit Cards

Paying with credit or debit card is fairly straightforward for customers. They simply enter in their cardholder information and click Pay. We give receipts to your customers after a successful payment.

Pay Invoice with Credit Card


Customers can pay with ACH just as easily as with credit cards. The key difference is that ACH payments will take several business days to clear. When customers are on a payment form they will select ACH as the payment information and then enter in their bank account and routing number.

Pay Invoice with ACH


Need help with your American Express payment gateway account? Please contact your American Express account manager.