Advanced Features Guide

Table Of Contents

Express Checkout Advanced Features Guide April 2012 59

Reference Transactions

Setting Up a Billing Agreement Using the Express Checkout API

You must set up a billing agreement using the Express Checkout API before you can use a

reference transaction.

Specify 0 as the amount of the purchase in SetExpressCheckout and call

CreateBillingAgreement if you only want to obtain a billing agreement ID for later use.

(Do not call DoExpressCheckoutPayment, because no payment is involved.) Otherwise,

call DoExpressCheckoutPayment to obtain the billing agreement ID and to initiate an

Express Checkout payment.

The following diagram shows the flow for obtaining a billing agreement ID during an Express

Checkout payment:

The numbered steps correspond to the circled numbers. Your site must take the specified

actions at each step, as follows: