Technical Overview

The graphic below offers a generalized view of the Express Checkout flow with a table of corresponding steps for each of the three integration points.

1aAfter selecting products to purchase, your customer clicks the Checkout with PayPal button on your website. This allows your customer to quickly skip entering shipping and billing information on your website.
1bIntegration Point 1

You make an API call to pass PayPal the transaction details. You then transfer the customer to PayPal via an HTTP redirect. Your customer is transferred to PayPal.

2aYour customer selects a shipping address and payment method stored with PayPal.
2bYour customer clicks Continue Checkout to approve the use of PayPal and is returned to your website.
2cIntegration Point 2

Your customer is transferred back to your website. PayPal transfers the customer via an HTTP redirect. You then make an API call to retrieve transaction details, such as shipping address, email address, and other information needed to fulfill your order.

3aYour customer finishes the checkout process on your website, reviews the order, and completes the order.
3bIntegration Point 3

When your customer places the order, you make an API call to PayPal to request payment. (Your customer does not see this step.) The payment transaction is initiated, and PayPal sends your customer an email receipt for the payment.

4You transfer your customer to your order confirmation page.