FakecreditcardHow Klarna test cards work
Klarna tests run in the playground environment with playground API credentials. When the Klarna widget asks for a card, use 4111 1111 1111 1111 with CVC 123 and expiry 12/28 or any later date. 4687 3888 8888 8881 starts a 3-D Secure flow, and it is also the debit card Klarna says to use for financing tests in the US.
Unlike card gateways, Klarna decides most outcomes from the customer. An email of the form customer+se@klarna.com (with the two-letter code of the market) gets an approved purchase, and adding +denied gets a hard decline. Other suffixes start the new-user sign-up flow or open disputes such as “return” or “goods not received”, so you can test your dispute handling too.
New users go through account creation with a phone number and a one-time code; in the playground any six-digit OTP except 999999 works. Each test account belongs to one market, so you can’t reuse the same email or phone number for Germany and Sweden. Klarna’s sample data also lists approved and denied phone numbers per country, and company data for B2B tests.
Customer emails that approve or deny
Klarna decides most outcomes from the customer, not the card. Replace ** with the two-letter code of the market, for example customer+se@klarna.com for Sweden or customer+de+denied@klarna.com for a denied purchase in Germany.
| Email pattern | Result |
|---|---|
| customer+**@klarna.com | Purchase accepted; an auth_token (valid 60 minutes) is returned for create_order |
| customer+**+denied@klarna.com | Hard decline: “Your purchase can not be accepted” |
| customer+**+new_user@klarna.com | New user sign-up flow |
| customer+**+disputed-return@klarna.com | Creates a dispute with reason “return” on each capture |
| customer+**+disputed-goods_not_received@klarna.com | Dispute with reason “goods not received” |
| customer+**+disputed-unauthorized_purchase@klarna.com | Dispute with reason “unauthorized purchase” |
In the playground any 6-digit OTP except 999999 works. In the US, enter SSN 123456789 when asked. For direct debit in Germany Klarna gives the sample IBAN DE11 5205 1373 5120 7101 31; for bank transfer pick “Demo Bank”. Klarna notes that denied flows can’t be tested in some markets, such as Sweden and Norway.
Testing Klarna payments step by step
- Get playground API credentials and point your integration at the playground environment.
- Start a session for an approved customer such as
customer+de@klarna.comand pay with the test card. - Repeat with the
+deniedemail to test how your checkout handles a rejected purchase. - Use
4687 3888 8888 8881to test the 3-D Secure step. - Test disputes with the
+disputed-emails and check your order management flow.
Common errors and fixes
- Denied email is approved
- Denied flows can’t be tested in some markets, such as Sweden and Norway. Use another market or ask Klarna merchant support.
- OTP rejected
- Any six-digit code works except 999999.
- Account belongs to another country
- Test accounts are tied to one market. Use a different email and phone number per country.
Sources
Every number on this page was copied from Klarna’s official documentation and passes the Luhn check. Checked October 2026; gateways change their test data from time to time, so if a number stops working, check the source:
Frequently asked questions
What is the Klarna test card number?
4111 1111 1111 1111 with CVC 123 and expiry 12/28 (or any future date) in the Klarna playground.
How do I test a denied Klarna purchase?
Use a customer email with +denied, for example customer+de+denied@klarna.com. It returns a hard decline.
Which SSN do I use for Klarna tests in the US?
Enter 123456789 when the playground asks for a Social Security Number.
Can I use these test cards on another gateway?
Usually not. Each gateway only recognises its own documented test numbers in its own sandbox. Some numbers, such as 4111 1111 1111 1111, appear in several lists, but the results they trigger differ. For format-only testing on your own forms, use our card generator.