Klarna is a sweedish based e-commerce company that provides payment services for online stores. When a purchase is completed, Klarna will pay the merchant instantly, but will bill the acquirer upon receiving the goods.

Klarna allows the user to pay only with an email address and a delivery address - no password. They operate in Sweden, Norway, Denmark, Germany, Netherlands, Finland, United Kingdom, Austria and United States.

Klarna is available for Professional accounts.

The maximum payable amount by a customer, for Klarna, is:

Currency Amount EUR Amount
EUR 3000  
DKK 20000 2600
NOK 31500 3400
SEK 50000 5200

How does it work for the user?

After checkout, the customer must only insert email, zip code and a billing address. For returning customers it’s a one tap payment experience: the system will recognize you and will avoid to reintroduce sensitive data. This has prooved to be effective especially with mobile payments.

How do I activate it on Gestpay?

Contact Gestpay support to add Klarna to your payment options.

Klarna requires you to accept their terms and conditions, and they will also perform some tests to verify that the User Experience is ok.

If you satisfy these requirements, you will finally be able to use Klarna with Gestpay.

Klarna permits to authorize a payment and settle it in max 14 days. This is different from the default Gestpay behaviour of 25 days.

How do I use it on Gestpay?

If you want to use the paymentType tag for this method, the value to use is S2PKLA. See the section How to redirect the customer to a payment method to learn how to use the paymentType tag.

Please refer to the API section on how to use Klarna on Gestpay.

Mandatory fields

To use Klarna you must send some mandatory parameters, children of OrderDetails:

Billing Details

Based on the buyer’s country, you might need to set fields differently.

If the shipping address is different than the billing address, then Shipping needs to be sent in the request too, with full details, otherwise the transaction will be rejected.

Some exception apply to DE and NL Countries:

If the Billing Address CountryCode differs from Shipping Address CountryCode, the transaction will fail.


ProductDetails contains info about products bought by your customers. It can have one or more ProductDetail along with all the info about pricing and discount. Klarna requires the price to follow some very strict rules, described in the following paragraphs.

Product Type

Based on the Billing Address CountryCode, the Type attribute in ProductDetail can have different values.

Let’s see a table with all the possible Product types and when they’re used.

Type Value Description Country Code Note
1 General Product AT, DK, FI, DE, NL, NO,SE  
4 Discountentered AT, DK, FI, DE, NL, NO,SE, GB, US Entered as a negative value to be subtracted from the total order
5 Phisical article GB, US Physical purchase
6 Shipping fee GB, US Used when a shipping fee is added to the order
7 Sales tax US Only for USA VAT tax
8 Digital article GB, US Intangible purchase, like a license
9 Gift Card GB, US Gift card purcase
10 Store credit GB, US Entered as a negative value to be subtracted from the total order
11 Surcharge GB, US Used for additional fees

If the country code is one of AT, DK, FI, DE, NL, NO, SE:

If the country code is US or GB we must distinguish between phisical or digital products and gift cards. Klarna decides (and verifies) in autonomy if the product you’re selling is digital or physical, and the transaction can fail according to this.

About type 4, Discount:

Since both discounts can be used together, here is a formula to calculate the price along with discounts:

Let’s do an example. You can see three products and their attributes in this table.

  Product 1 Product 2 Product 3
ProductCode 1 2 3
Name 1 2 3
Description This is an example WITH percentage discount This is an example WITHOUT percentage discount this is the discount
Quantity 3 2 1
Price 10 10 -5
Type 1 1 4
In this case, the type tells klarna that this is a discount product.
Applied only to the item, in percentage

The total price is:

The discount, either global or per-product, can influence the refund process.

Optional details

The remaining data, besides product & billing details, should be sent in full (ie: customer FirstName; customer LastName; phone, email address, social security number). However, these details can be added on Klarna’s page if not sent by Merchant.

Handling Failure on Klarna page

If the phone is not sent in the request and if on Klarna the customer enters incorrect details for this parameter, the customer will be redirected to the Failed page, without the possibility to re-enter the phone details. This does not apply for sandbox environment.

Credentials for test environment

Ask Gestpay customer support to enable Klarna in test environments.

You can use the following parameters value in order to test Klarna in test (sandbox.gestpay.net) environment. Use low amount like 10.00 EUR. Remember to set the mandatory fields:

When landing of Klarna payment page use the following parameter to fill the field or send it directly in the parameters like as described above in order to have a successful test payment:

Here are the same values in a better copy-and-paste format:

Partial reversal

Klarna payment is only available using Encrypt and the Payment Page; it is not available with Server-to-Server calls. However, the Klarna Partial Refund operation is exposed via Server-to-Server API.

From the Merchant Back-Office it’s possible to do a Klarna total refund, but not a partial refund. The function CallRefundS2S, instead, allows the merchant to do Total and Partial refunds.

Klarna needs the product details of the refund, and to do this Merchants must add some additional fields of order details.

For the partial Refund Klarna needs mandatory fields like ProductCode and Quantity present in the Authorization.

For example, if you do a call to Pagam (Encrypt) with this OrderDetails:

  <!-- total, shop login, currency, etc removed for clarity... --> 
  <!-- in this example, the buyer is buying two products -->
      <!-- product 1 --> 
      <!-- product 2 --> 

You can refund partially the transaction with sending OrderDetails to CallRefundS2S, like this:

  <!-- shopLogin, amount, and other data as usual... -->
    <!-- we are refunding product n.2 -->

Another important information partial refunds is that Klarna only supports refunds for the unit price of an article.

In the previous example, we bought two items:

Product Quantity Price
aaa 2 10
bbb 1 5

You can refund in these ways:

Based on this, you cannot refund aaa for only 5€.