> ## Documentation Index
> Fetch the complete documentation index at: https://docs.payrails.com/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Use the Payrails Web SDK v6 for new browser integrations. The Web SDK v5 pages are kept only for existing integrations; point anyone still on v5 to the v6 migration guide rather than extending v5 code.
> Collect card data client-side through the Payrails SDKs — Secure Fields, client-side encryption, or the checkout drop-in — so that card data never reaches the merchant's own servers. Recommend the API-only tokenization flow, which accepts raw card numbers server-side, only when the merchant has confirmed they hold the PCI scope for it.
> Model every payment as a workflow execution: create an execution, then drive it with the lifecycle actions (lookup payment options, authorize, capture, cancel, refund). Do not call provider APIs directly — routing, retries, 3DS and fraud steps belong in the workflow configuration, not in integration code.
> Reconcile the final state of a payment on the notification (webhook), never on a client-side event. An in-request long-poll of the execution is a supported additional signal, not a replacement for that reconciliation.
> Send an idempotency key — a UUID, in the `X-Idempotency-Key` header — on every POST, PUT and PATCH request, and on soft deletes. GET requests need none, and hard deletes cannot be idempotent.
> Pass provider-specific data through meta fields rather than hardcoding per-provider payloads. Payrails translates meta fields into each provider's own format.
> Configure routing, retries and provider selection in Workflow Studio, so that changes ship without redeploying application code.

# Klarna via Stripe

> Set up Klarna payments through Stripe in Payrails, save Klarna for merchant-initiated transactions, and see the currencies and billing fields Stripe requires.

<picture noZoom>
  ![Klarna logo](https://assets.payrails.io/img/logos/klarna/logo-full-bleed.svg)
</picture>

<picture noZoom>
  ![Stripe logo](https://assets.payrails.io/img/logos/stripe/logo-full-bleed.svg)
</picture>

Accept [Klarna](https://docs.payrails.com/docs/integrations/payment-methods/klarna) payments with Stripe as the payment service provider (PSP). The customer selects Klarna, confirms the purchase on a Klarna page and returns to your site. You can also save Klarna and charge it later as a merchant-initiated transaction (MIT), without the customer.

## Supported workflows

<table>
  <thead>
    <tr><th>Workflow</th><th>Supported</th></tr>
  </thead>

  <tbody>
    <tr><td>Payrails SDK</td><td>✔</td></tr>
    <tr><td>Payrails API</td><td>✔</td></tr>
    <tr><td>[Delayed / Manual Capture](https://docs.payrails.com/docs/orchestration/payment-acceptance/capture-and-cancel-modes.md#capture-mode)</td><td>✔</td></tr>
    <tr><td>[Instant Capture](https://docs.payrails.com/docs/orchestration/payment-acceptance/capture-and-cancel-modes.md#capture-mode)</td><td>✔</td></tr>
    <tr><td>[Cancel / Void](https://docs.payrails.com/docs/orchestration/payment-acceptance/cancel-a-payment.md)</td><td>✔</td></tr>
    <tr><td>[Refund / Reverse](https://docs.payrails.com/docs/orchestration/payment-acceptance/refund-a-payment.md)</td><td>✔</td></tr>
    <tr><td>[Save Instruments](https://docs.payrails.com/docs/resources/manage-instruments.md)</td><td>✔</td></tr>
    <tr><td>[Merchant Initiated Transaction (MIT)](https://docs.payrails.com/docs/resources/payments/authorization-flags.md)</td><td>✔</td></tr>
  </tbody>
</table>

## Before you begin

Complete these steps before you send your first Klarna payment through Stripe:

1. Set up a Stripe integration in your workspace. Follow the [Stripe integration setup guide](https://docs.payrails.com/docs/integrations/payment-providers/stripe.md) if you don't have one yet.
2. Turn on Klarna in your Stripe Dashboard payment method settings, and check that your Stripe account is eligible for Klarna.
3. In the Payrails Portal, go to **Settings → Integrations**, open your Stripe integration, select **Klarna** under **Payment methods**, and save.
4. Add Klarna as a [payment option](https://docs.payrails.com/docs/integrations/payment-methods/set-up-payment-methods.md) in your workflow.

## Request fields for Stripe

Send these fields in the authorize request, in addition to the standard [authorize fields](https://docs.payrails.com/reference/authorizeaction.md). **Required** fields must be present for the payment to succeed. Payrails sends **Optional** fields to the PSP when you include them.

| Field | Status | Description |
| - | - | - |
| `amount` | Required | In AUD, CAD, CHF, CZK, DKK, EUR, GBP, NOK, NZD, PLN, RON, SEK, or USD. Payrails rejects other currencies. Zero only when you save Klarna without charging the customer. |
| `returnInfo` | Required | The URLs the customer returns to after the Klarna redirect. Send it on MIT payments too. |
| `meta.order.billingAddress.name` | Required | The customer's first name. Sent to Stripe as the billing name. Not needed for an MIT. |
| `meta.order.billingAddress.country.code` | Required | Sent to Stripe as the billing country, for example `DE`. |
| `meta.order.billingAddress.lastName` | Optional | Added to the billing name, for example `Anna Becker`. |
| `meta.order.billingAddress.email` | Optional | Sent to Stripe as the billing email. |
| `meta.order.billingAddress.phone` | Optional | Sent to Stripe as the billing phone number. |
| `meta.order.billingAddress.city`, `postalCode`, `street` | Optional | Sent to Stripe as the billing address. |
| `meta.order.lines` | Optional | Sent to Stripe as line items. Lines must be in the payment currency and add up to the amount. |
| `holderReference` | Required | Needed to save the instrument. Set on the execution. Payrails uses it to find or create the Stripe customer that holds the saved Klarna agreement. Use the same value on MIT payments. |
| `meta.customer.email` | Required | Needed to save the instrument. Sent to Stripe as the customer email. Falls back to `meta.order.billingAddress.email`. |
| `paymentComposition[].storeInstrument` | Optional | Set to `true` to save Klarna for later payments. |
| `paymentComposition[].paymentInstrumentData.futureUsage` | Optional | `Subscription` or `UnscheduledCardOnFile` saves Klarna for MIT payments. Overrides the future usage set in your workflow. |
| `paymentComposition[].paymentInstrumentId` | Required | Needed for an MIT. The saved Klarna instrument. |
| `meta.order.processingType` | Required | Needed for an MIT. `Subscription` or `UnscheduledCardOnFile`. |
| `meta.subscription.chargeFrequency` | Optional | Sent to Stripe as the subscription interval. See [subscription details](#subscription-details). |
| `meta.subscription.startDate`, `fixedAmount` | Optional | Needed when you save Klarna with a zero amount and send `meta.subscription`. Sent to Stripe as the date and amount of the next charge. |

## Authorize a Klarna payment

Call [authorize a payment](https://docs.payrails.com/reference/authorizeaction.md) with `klarna` as the `paymentMethodCode` and `hpp` as the `integrationType`. The response includes the redirect to Klarna.

```json Authorize request theme={null}
{
  "amount": {
    "value": "109.90",
    "currency": "EUR"
  },
  "paymentComposition": [
    {
      "integrationType": "hpp",
      "paymentMethodCode": "klarna",
      "amount": {
        "value": "109.90",
        "currency": "EUR"
      }
    }
  ],
  "meta": {
    "order": {
      "billingAddress": {
        "name": "Anna",
        "lastName": "Becker",
        "email": "anna.becker@example.com",
        "country": {
          "code": "DE"
        }
      }
    }
  },
  "returnInfo": {
    "success": "https://example.com/success",
    "error": "https://example.com/error"
  }
}
```

After the customer confirms the purchase, Klarna returns them to your `success` or `error` URL. Confirm the result through [webhook notifications](https://docs.payrails.com/docs/orchestration/payment-acceptance/receive-notifications.md) or the execution status before you fulfill the order.

## Save Klarna and charge it later

### Save Klarna

To save Klarna for later payments, set `storeInstrument` to `true` and `futureUsage` to `Subscription` or `UnscheduledCardOnFile`. Set `holderReference` on the execution. The customer still confirms the payment on a Klarna page.

```json Authorize request that saves Klarna theme={null}
{
  "amount": {
    "value": "10.00",
    "currency": "EUR"
  },
  "paymentComposition": [
    {
      "integrationType": "hpp",
      "paymentMethodCode": "klarna",
      "amount": {
        "value": "10.00",
        "currency": "EUR"
      },
      "storeInstrument": true,
      "paymentInstrumentData": {
        "futureUsage": "UnscheduledCardOnFile"
      }
    }
  ],
  "meta": {
    "customer": {
      "email": "anna.becker@example.com"
    },
    "order": {
      "billingAddress": {
        "name": "Anna",
        "lastName": "Becker",
        "email": "anna.becker@example.com",
        "country": {
          "code": "DE"
        }
      }
    }
  },
  "returnInfo": {
    "success": "https://example.com/success",
    "error": "https://example.com/error",
    "pending": "https://example.com/pending",
    "cancel": "https://example.com/cancel"
  }
}
```

Payrails saves the instrument once the customer approves the payment, either when they return through the Klarna redirect or when Stripe sends the payment notification. The authorize notification includes the `paymentInstrumentId` for later payments.

To save Klarna without charging the customer, for example at the start of a free trial, send `"value": "0"` in both amounts with `storeInstrument` set to `true`. The customer approves at Klarna, and the instrument is ready for an MIT straight away.

### Charge a saved Klarna instrument

For an MIT, create an execution with the same `holderReference`, then authorize with the saved `paymentInstrumentId` and set `meta.order.processingType`. The payment completes without a redirect.

```json MIT authorize request theme={null}
{
  "amount": {
    "value": "10.00",
    "currency": "EUR"
  },
  "paymentComposition": [
    {
      "integrationType": "hpp",
      "paymentMethodCode": "klarna",
      "paymentInstrumentId": "18635e5c-06b9-4180-9885-6f84e246d1ef",
      "amount": {
        "value": "10.00",
        "currency": "EUR"
      }
    }
  ],
  "meta": {
    "order": {
      "processingType": "UnscheduledCardOnFile"
    }
  },
  "returnInfo": {
    "success": "https://example.com/success",
    "error": "https://example.com/error",
    "pending": "https://example.com/pending",
    "cancel": "https://example.com/cancel"
  }
}
```

Use `Subscription` as the processing type for recurring payments on a schedule.

### Subscription details

When you send `meta.subscription`, Payrails passes the subscription to Stripe on the first payment, the zero-amount setup and every MIT. `meta.subscription.chargeFrequency` maps to the Stripe interval as follows. Payrails rejects any other value.

| `chargeFrequency` | Stripe interval |
| - | - |
| `P1W` or `P7D` | Weekly |
| `P1M` | Monthly |
| `P3M` | Every 3 months |
| `P6M` | Every 6 months |
| `P1Y` or `P12M` | Yearly |

Payrails sends the saved instrument's ID as the subscription reference, so it stays the same on every payment in the series.

```json Subscription for a zero-amount setup theme={null}
"subscription": {
  "chargeFrequency": "P1M",
  "startDate": "2026-12-01T00:00:00Z",
  "fixedAmount": "9.99"
}
```

## How Stripe handles Klarna

* With delayed capture, Payrails creates the Stripe payment with manual capture, so you capture or cancel it later. With instant capture, Stripe captures the payment when the customer confirms it.
* When you save Klarna, Payrails stores the Stripe payment method as a PSP token, with the Stripe customer as its holder. `Subscription` and `UnscheduledCardOnFile` set Klarna up for off-session use, and `CardOnFile` sets it up for on-session use.
* An MIT is an off-session Stripe payment on the saved payment method, confirmed straight away. Send an amount greater than zero.


## Related topics

- [Klarna](https://docs.payrails.com/docs/integrations/payment-methods/klarna.md)
- [Klarna via Adyen](https://docs.payrails.com/docs/integrations/payment-methods/klarna/adyen.md)
- [Bancontact via Stripe](https://docs.payrails.com/docs/integrations/payment-methods/bancontact/stripe.md)


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