Accept a Klarna payment

When a customer accepts Klarna in your app, a webview for a customer to authenticate their payment appears. The customer then returns to your app, and you can immediately confirm whether the payment succeeded or failed.

# Available as a gem
sudo gem install stripe

# If you use bundler, you can add this line to your Gemfile
gem 'stripe'

import UIKit
import StripePaymentsUI

@main
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        StripeAPI.defaultPublishableKey = 
"pk_test_TYooMQauvdEDq54NiTphI7jx"
        // do any other necessary launch configuration
        return true
    }
}

curl https://api.stripe.com/v1/payment_intents \
  -u "
sk_test_BQokikJOvBiI2HlWgH4olfQ2
:" \
  -d "payment_method_types[]"=klarna \
  -d amount=1099 \
  -d currency=eur

import UIKit
import StripePaymentsUI

class CheckoutViewController: UIViewController {
  var paymentIntentClientSecret: String?

  func startCheckout() {
      // Request a PaymentIntent from your server and store its client secret
  }
}}

let paymentIntentParams = STPPaymentIntentParams(clientSecret: paymentIntentClientSecret)
paymentIntentParams.paymentMethodParams = klarnaParams
paymentIntentParams.shipping = shippingDetails

STPPaymentHandler.shared().confirmPayment(paymentIntentParams, with: self) { (handlerStatus, paymentIntent, error) in
    switch handlerStatus {
    case .succeeded:
        // Payment succeeded

    case .canceled:
        // Payment was canceled

    case .failed:
        // Payment failed

    @unknown default:
        fatalError()
    }
}

Failed payments

Klarna takes into account multiple factors when deciding to accept or decline a transaction (for example, length of time buyer has been using Klarna, outstanding amount customer has to repay, value of the current order).

When the customer selects a deferred payment method, Klarna performs a risk assessment before accepting the transaction. Klarna might decline the transaction due to unsatisfactory risk assessment result, the transaction amount involved, or the customer having a large outstanding debt. As such, we recommend that you present additional payment options such as card in your checkout flow. In these cases, the PaymentMethod is detached and the PaymentIntent object’s status automatically transitions to requires_payment_method.

Customers are expected to complete the payment within 48 hours after they’re redirected to the Klarna site. If no action is taken after 48 hours, the PaymentMethod is detached and the PaymentIntent object’s status automatically transitions from requires_action to requires_payment_method.

In these cases, inform your customer to try again with a different payment option presented in your checkout flow.

Klarna rate limits

API requests to Klarna are subject to additional rate limits beyond Stripe’s API-wide rate limits. These limits can differ depending on the shape of the API requests that you make. In general, if you make more than around 360 requests per minute, you may see some rate limiting in the form of responses with HTTP status code 400 or 402. Please contact us for more details if you’re concerned that your usage may reach these levels, as Klarna may be able to increase these limits on a case by case basis.

Error messaging

Failed Klarna payments normally return one of the following failure codes. These codes show in the last_payment_error API object.