Direct API In-Store without Webhooks

Overview

Affirm’s In-Store Integration allows merchants to offer flexible payment options directly within their point-of-sale (POS) systems. This variant is designed for merchants who prefer not to maintain a public webhook endpoint, or whose infrastructure (e.g., firewalls, security policies) makes webhook delivery unreliable.

Instead of relying on webhook callbacks, merchants complete the transaction flow using a manual confirmation process paired with on-demand API authorization calls.

How It Works

Integration Flow Chart

The in-store workflow without webhooks follows these steps:

1. Select Affirm at Checkout

The sales associate selects Affirm as the payment method on the POS terminal.

2. Create Checkout Object

The POS system calls Affirm’s Store API (/api/v2/checkout/store) with billing details, order totals, and metadata.

Affirm returns a checkout_id and sends the customer a checkout link via SMS (production) or email (sandbox/live fallback).

3. Customer Completes Application

The customer opens the link on their device, reviews terms, and confirms or declines the loan application.

4. Customer Notifies Associate

Once approved, the customer informs the in-store associate that they have completed their Affirm application.

5. Manual Authorization

The associate finalizes the order by instructing the POS to make an Authorization API call using the saved checkout_id.

6. Order Confirmation

If authorization succeeds, the merchant saves the customer’s loan ID, and the POS displays a success message.

If authorization fails, the associate is shown an error message and can advise the customer accordingly.

7. Order Status Update

The POS updates the order status to reflect that the transaction is complete.