PSP
A PSP (payment service provider) connects your store to acquirers and payment methods and handles the gateway, security, and payouts.
What is a PSP?
A PSP (payment service provider) is a payment intermediary that connects your store to acquirers, card networks, and alternative payment methods, so you can accept payments without signing a separate contract with each method. A PSP usually bundles the payment gateway itself with a range of services on top: PCI DSS handling, tokenization of card data, fraud screening, and settlement of payouts. A pure gateway only covers the technical transmission of transaction data — a PSP covers the whole chain from payment to payout.
Why does a PSP matter?
The PSP sits in the middle of checkout and determines which payment methods you can offer, how high the fees are, and how smoothly the payment completes. A poor match leads to declined payments, missing local methods, or needless friction that lowers your completion rate. The PSP is also your responsible party for SCA under PSD2: it triggers 3-D Secure at checkout so strong customer authentication is handled correctly without causing unnecessary drop-off.
Common use cases
- Choosing a provider at launch — compare fees, supported cards, and local methods like MobilePay.
- Adding new payment methods such as Apple Pay, PayPal, or buy-now-pay-later.
- Handling SCA/3-D Secure to comply with PSD2 in the European market.
- Reconciling payouts and fees between the PSP, bookkeeping, and Shopify.
- Debugging declined payments or missing orders in checkout.
Shopify perspective
Shopify Payments is Shopify’s built-in PSP, technically powered by Stripe. If you instead use a third-party PSP such as Adyen, Mollie, PayPal, or Klarna, Shopify charges an extra transaction fee on top of the PSP’s own fees — typically 2% on Basic, 1% on Shopify, and 0.5% on Advanced. So calculate the total cost across both layers, and always test a realistic order with 3-D Secure enabled before going live.