You have two different ways to present Klarna in your checkout, depending on whether you build your own payment form or rely on Paytrail’s Hosted Payment Page.

If you manage your own checkout UI, you can integrate Klarna in one of the following ways:

Use Klarna's Web SDK to build the payment selector and offer Klarna as a payment option in your checkout.

• Build the payment form using Klarna API's.

Alternatively, you can use Paytrail’s List Payment Providers or List Grouped Payment Providers endpoints to retrieve available payment methods and Klarna presentation assets to build your payment form.

Note that, currently, Paytrail’s API only supports returning name and icon assets. For the best checkout experience for your customers, we recommend implementing Klarna’s Web SDK.

If you rely on Paytrail’s Hosted Payment Page and don’t build your own payment selector, Klarna will be shown by default.

Please see Paytrail Payment API documentation for more details.