Klarna Shipping Assistant

Klarna Shipping Assistant

Klarna Shipping Assistant for WooCommerce is not compatible with Klarna External Payment Methods.


Klarna Shipping Assistant for WooCommerce (previously Klarna Shipping Service) is an add-on plugin to Klarna Checkout for WooCommerce. This add-on plugin makes it possible to display shipping options in the Klarna Checkout (KCO) iframe provided by your Transport Management System (TMS).


English: use the support form on krokedil.com to get help.

Svenska: använd supportformuläret på krokedil.se för att få hjälp.

Helpful information before you contact us can be found in the How to prepare a support ticket article.

Useful internal links

Technical information – plugin data and changelog

Useful external links

English product page on krokedil.com

Svensk produktsida på krokedil.se


  • Your Klarna account needs to be activated for Klarna Shipping Assistant with TMS before using this plugin.
  • Requires WooCommerce together with Klarna Checkout for WooCommerce to be used.
  • Klarna Shipping Assistant is used for handling the shipping methods in your store. However, it is still required to have at least one native WooCommerce shipping method active for each shipping zone you enabled KSA.
  • HTTPS is not required on your site, but strongly recommended.


To install this plugin you first need to have Klarna Checkout for WooCommerce installed.

  1. Download the .zip file
  2. Go to: WordPress Admin → Plugins → Add New and upload the file via Upload plugin.
  3. Install Now and Activate.


  1. Navigate to WooCommerce > Settings > Payments and select Klarna Checkout.
  2. Make sure that the checkbox Shipping methods in iframe is ticked in the Shipping settings section.
  3. Save the payment gateway settings.
  4. Navigate to WooCommerce > Settings > Shipping.
  5. For every shipping zone you have created you need to add Klarna Shipping Assistant as a new shipping method.
  6. Make sure that the Klarna Shipping Assistant shipping method is the first shipping method in the list of available shipping methods for the zone that you are configuring.

If everything is working fine you should be able to see the shipping methods provided by your TMS in the KCO iframe now:

Each TMS system has its own configuration process to connect to Klarna.

Shipping data in WooCommerce order

When an order has been created in WooCommerce, the name and price of the selected shipping method in the KCO iframe is added to the order.

The entire shipment data sent from Klarna for the order is also stored in the WooCommerce order, as an order meta field with the name _kco_kss_data. This data is stored as a json object with the following structure:

	"id": "id-1000",
	"name": "Pickup Box",
	"price": 500,
	"tax_amount": 0,
	"tax_rate": 0,
	"preselected": false,
	"shipping_method": "BoxUnreg",
	"delivery_details": {
		"carrier": "instabox",
		"class": "economy",
		"product": {
			"name": "MyPack",
			"identifier": "10"
		"pickup_location": {
			"id": "loc-2",
			"name": "Coop Loet",
			"address": {
				"street_address": "Storgatan 59",
				"postal_code": "97232",
				"city": "Luleu00e5",
				"country": "se"
	"tms_reference": "100"

Product dimensions and shipping classes

When you have KSA activated it adds the product dimensions and shipping classes to the cart items. Dimensions the plugin looks for and adds are weight, width, height and length.

The shipping options presented in the checkout is based on your TMS configuration for the dimensions above.

Free shipping coupons

tag named ksa_free_shipping is sent to Klarna if a coupon code is used that enables the customer free shipping.

Different TMS is handling this in different ways so get in touch with your TMS-system to know how they handle free shipping coupons and how to set it up correct.

Tax settings

Since Klarna takes over the shipping cost fully with Klarna Shipping Assistant it is important that the tax settings in WooCommerce that apply to shipping matches what you have in the TMS system.

For example, if you have 25% tax applied to shipping costs in the TMS system, this tax needs to exist in WooCommerce. It is also recommended to set the tax calculations for shipping to only use this tax class to prevent any issues when using multiple different taxrates in WooCommerce.

First you need to create the tax that you want to use for the shipping method. 

After this you will want to set this tax class as the only one that can be applied to shipping.

If you have “Shipping tax class based on cart items”, it could cause a mismatch between the Klarna order and the WooCommerce order due to different taxes being applied to the shipping price in Klarna then to WooCommerce.

Subscription support

Subscriptions are supported with Klarna Shipping Assistant.

However, there might occur issues with your TMS or a third party plugin. One example is when the TMS tries to reuse the ID for the shipment of the first item for consecutive shipments, which will then fail.

When using the plugin Krokedil Shipping Connector together with Klarna Shipping Assistant this is not an issue as the shipment ID is not reused.

Tracking ID & Tracking URL reporting to Klarna

The Tracking information is sent to Klarna when the order is set as “Completed” in WooCommerce through the Klarna Order Management plugin. In order to send the Tracking data in this sequence to Klarna you will need to save the Tracking ID and the Tracking URL of the shipment to the order as a post meta before the order is set as “Completed” in WooCommerce. The post meta key we are expecting is _kss_tracking_id and _kss_tracking_url.

No booking of shipments

This plugin enables the possibility to display the shipping options provided by your TMS in the Klarna Checkout iframe. However, the actual booking of the shipment in your transport administration system is not handled in this plugin. There are a lot of TMS services available and every system has their own API. That’s why we don’t to connect to a specific TMS in this plugin.

However, if you use Klarna Shipping Assistant and have nShift (previously Unifaun) as a logistics partner, you can use our Krokedil Shipping Connector to book deliveries in Unifauns sytemprint shipping labels and see tracking link and status of delivery directly in your WooCommerce store.

Klarna Shipping Assistant is also compatible with the plugin Unifaun för WooCommerce by Redlight Media as well as Shipmondo.

Compatibility issues


Currently there are issues when using a giftcard and Klarna Shipping Assistant together.

Since the plugin do not use the callback, we have to remove the shipping lines from the order data we send to Klarna. This causes us to either have to send a negative order value or an incorrect order value when applying a giftcard that covers the entire order, due to the shipping line cost not being added to the order data.