Pay-by-bank (one-time)

Two steps to initiate a one-time payment. nrich uses SEPA Instant where the bank supports it, with automatic fallback to standard SEPA Credit Transfer.

Step 1

Create a Widget link for the payment

Step 2

Fetch the payment receipt

Step 1: Create the Widget link

POST https://api.finx-s.qwist.cloud/onetime/payment

{
  "redirect_uri": "https://my-app.example.com/callback",
  "payment": {
    "creditor": {
      "iban": "DE89370400440532013000",
      "name": "Acme GmbH"
    },
    "amount": {
      "value": 149.99,
      "currency": "EUR"
    },
    "purpose": "Invoice INV-2025-0042"
  }
}

Required parameters:

Parameter	Description
`redirect_uri`	Where the user is returned after the flow.
`payment.creditor.iban`	IBAN of the recipient account.
`payment.creditor.name`	Name of the recipient (individual or business).
`payment.amount.value`	Amount to transfer.
`payment.amount.currency`	Currency code (e.g. `"EUR"`).
`payment.purpose`	Purpose text shown in the recipient's bank statement. Max 140 characters.

Optional parameters:

payment.debtor.iban - IBAN of the user's account. Pre-selects their bank, skipping bank selection:

{
  "payment": {
    "debtor": {
      "iban": "DE12500105170648489890"
    }
  }
}

📘
Improve conversion with debtor IBAN
If you know the user's IBAN - for example, because they entered it during onboarding - pass it here. The Widget skips bank selection and takes the user directly to authentication. This is the most effective conversion optimisation for payment flows.

Response:

{
  "location": "https://widget.qwist.cloud/?token=eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
  "id": "5e8c3f2a-9d4b-4f7e-a1c6-3b8d2e9f5a1c"
}

Store the id - this is your receipt ID for step 2. It is also returned as flow_id in the callback after the user completes the payment.

Forward the user to location via a redirect or iframe overlay.

After the user selects their bank, logs in, and confirms the payment with SCA, they are redirected to your redirect_uri with success=true, flow_id, and optionally abort=true if they cancelled.

Step 2: Fetch the payment receipt

See Fetching your Payment Receipt for the endpoint and response reference.