What it does
Affirm provides merchant checkout financing and consumer payment plans whose terms and eligibility vary by purchase. Merchants apply for a financing programme, then add Affirm to their checkout. The US merchant offer charges transaction-based fees, with the rate supplied after the business submits its details.
Applying as a merchant
The US onboarding flow asks for the store, business, owner and bank details, along with the financing package and confirmation about prohibited products. A live website is required. Creating a dashboard account is only the start: orders and integration access remain restricted until Affirm evaluates and approves the business.
Once approved, the merchant can connect a supported commerce platform or use Affirm's developer interface for a custom checkout. A customer selects Affirm, receives available plan options and confirms a schedule before the merchant processes the order.
Merchant fees and customer interest
Affirm's merchant charge combines a percentage and a per-transaction amount. The programme, business size and risk profile affect the rate. Its US merchant FAQ lists no integration, annual or monthly fee. Merchant processing fees are not refunded when the purchase is refunded.
For US shoppers, the published financing range is 0% to 36% annual percentage rate (APR), subject to eligibility; Pay in 4 is 0% APR. Purchase size and merchant affect the options, and a down payment may be required. US applicants need a Social Security number and a US or territory phone number that receives texts. Residency and minimum-age rules also apply. The actual offered schedule determines the purchase's financing cost.
Strengths
- Merchants can issue full or partial refunds through their commerce platform or Merchant Portal
- Customers can manage repayments online, in the app or through AutoPay
Watch out for
- Merchant order and integration access require business approval
- Merchant discount and transaction fees are not returned on refunds
Best for
- Merchants assessing a pay-over-time checkout integration and its fee structure
Sources
- Affirm for Merchants: Customer Financing and Buy Now Pay Later (Oct 28, 2026)
- Getting Started with Affirm: Signing Up and Account Creation (Oct 28, 2026)
- Getting Started with Affirm: Frequently Asked Questions Before Starting (Oct 28, 2026)
- How to Use Affirm for Buy Now Pay Later Payment Plans (Oct 28, 2026)
- Loan Application Process | Affirm Help Center (Oct 28, 2026)