Accept a Klarna payment
Learn how to accept Klarna, a global buy now, pay later payment method.
Unified line items with Klarna
To optimize approval rates when you integrate with Klarna, include line_
data to represent what’s in a shopper’s cart. For early access, see Payments line items.
When a customer chooses Klarna in your app, a webview for them to authenticate their payment appears. After the customer is redirected back to your app, you can immediately confirm whether the payment succeeded or failed.
Notiz
Before starting your integration, check that your account is eligible for Klarna on the Payment methods settings.
Set up StripeServer-sideClient-side
Server-side 
This integration requires endpoints on your server that talk to the Stripe API. Use our official libraries for access to the Stripe API from your server:
Client-side 
The React Native SDK is open source and fully documented. Internally, it uses the native iOS and Android SDKs. To install Stripe’s React Native SDK, run one of the following commands in your project’s directory (depending on which package manager you use):
Next, install some other necessary dependencies:
- For iOS, navigate to the ios directory and run
pod install
to ensure that you also install the required native dependencies. - For Android, there are no more dependencies to install.
Stripe initialization
To initialize Stripe in your React Native app, either wrap your payment screen with the StripeProvider
component, or use the initStripe
initialization method. Only the API publishable key in publishableKey
is required. The following example shows how to initialize Stripe using the StripeProvider
component.
import { StripeProvider } from '@stripe/stripe-react-native'; function App() { const [publishableKey, setPublishableKey] = useState(''); const fetchPublishableKey = async () => { const key = await fetchKey(); // fetch key from your server here setPublishableKey(key); }; useEffect(() => { fetchPublishableKey(); }, []); return ( <StripeProvider publishableKey={publishableKey} merchantIdentifier="merchant.identifier" // required for Apple Pay urlScheme="your-url-scheme" // required for 3D Secure and bank redirects > // Your app code here </StripeProvider> ); }
Create a PaymentIntentServer-sideClient-side
Stripe uses a PaymentIntent object to represent your intent to collect payment from a customer, tracking your charge attempts and payment state changes throughout the payment process.
Server-side 
First, create a PaymentIntent
on your server and specify the amount to collect and the currency. If you already have an integration using the Payment Intents API, add klarna
to the list of payment method types for your PaymentIntent
.
Client-side 
A PaymentIntent includes a client secret. You can use the client secret in your React Native app to securely complete the payment process instead of passing back the entire PaymentIntent object. In your app, request a PaymentIntent from your server and store its client secret.
function PaymentScreen() { // ... const fetchPaymentIntentClientSecret = async () => { const response = await fetch(`${API_URL}/create-payment-intent`, { method: 'POST', headers: { 'Content-Type': 'application/json', }, body: JSON.stringify({ currency: 'eur', }), }); const {clientSecret} = await response.json(); return clientSecret; }; return <View>...</View>; }
Submit the payment to StripeClient-side
Submitting the payment to Stripe requires the client secret from the PaymentIntent that you created. Include it in your call to confirmPayment
:
import {Picker} from '@react-native-picker/picker'; import {confirmPayment} from '@stripe/stripe-react-native'; export default function MyPaymentScreen() { const handlePayPress = async () => { // Fetch the intent client secret from the backend. // See `fetchPaymentIntentClientSecret()`'s implementation above. const clientSecret = await fetchPaymentIntentClientSecret(); const {error, paymentIntent} = await confirmPayment(clientSecret, { paymentMethodType: 'Klarna' }, }); if (error) { console.log('Payment confirmation error', error.message); // Update UI to prompt user to retry payment (and possibly another payment method) } else if (paymentIntent) { Alert.alert('Success', `The payment was confirmed successfully!`); } };
Test Klarna integration
Below, we have specially selected test data for the currently supported customer countries. In a sandbox, Klarna approves or denies a transaction based on the supplied email address.
Two-step authentication
Any six digit number is a valid two-step authentication code. Use 999999
for authentication to fail.
Repayment method
Inside the Klarna flow, you can use the following test values to try various repayment types:
Type | Value |
---|---|
Direct Debit | DE11520513735120710131 |
Bank transfer | Demo Bank |
Credit Card |
|
Debit Card |
|
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_
.
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_
to requires_
.
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.
Vorsicht
Before the 2023-08-16
API version, every Klarna error reported as payment_intent_authentication_failure. Make sure your API version is up to date to see the detailed errors listed below.
Failure code | Explanation |
---|---|
payment_method_customer_decline | The customer cancelled the checkout on Klarna’s page |
payment_method_provider_decline | Klarna declined the customer’s payment |
payment_intent_payment_attempt_expired | The customer never completed the checkout on Klarna’s page, and the payment session has expired |
payment_method_not_available | An unexpected error occurred when trying to use Klarna |