Initiate a terminal payment

Send a card-present payment request to a specific terminal device. The payment is dispatched to the merchant's POS connector which forwards it to the PAX terminal.

Device Selection: You must provide a device_id. Use List Terminal Devices to discover available devices and their IDs. Even merchants with a single terminal must pass the device_id explicitly — there is no auto-routing fallback.

Invoice Association: invoice_id is optional. Omit it for walk-in or ad-hoc payments where no pre-existing invoice exists.

The response returns immediately with status requested. Subscribe to terminal webhooks (billing.terminal_payment.succeeded, billing.terminal_payment.declined, etc.) to receive the outcome asynchronously.

Related endpoints

• GET /terminal-payments — List terminal payments
• GET /terminal-payments/{id} — Retrieve a terminal payment
• POST /terminal-payments/{id}/cancel — Cancel a terminal payment
• POST /terminal-payments/{id}/refund — Refund a terminal payment
• POST /terminal-payments/{id}/void — Void a terminal payment

Common errors

• 400 invalid_request — malformed payload or failed validation.
• 401 unauthenticated — missing, malformed, or revoked API key.
• 403 permission_denied — key lacks the required scope, or the resource belongs to a different merchant.
• 409 conflict — Idempotency-Key collision with a different body, or a concurrent state-transition conflict.
• 422 unprocessable_entity — business-rule failure (for example, refunding more than the original charge).

Idempotency

Pass an Idempotency-Key header (UUID v4 recommended) to make retries safe. Keys are valid for 24 hours; see the idempotency guide.

curl -X POST "https://api.revkeen.com/v2/terminal-payments" \  -H "x-api-key: $REVKEEN_API_KEY" \  -H "Content-Type: application/json" \  -d '{    "device_id": "d1e2f3a4-b5c6-7890-abcd-ef1234567890",    "amount_minor": 5000,    "currency": "GBP",    "invoice_id": "00000000-0000-0000-0000-000000000000",    "reference": "walk-in-sale-001"  }'

{
  "data": {
    "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08",
    "invoice_id": "f4c4edb8-11e0-4b33-bcc1-482dc59ebb32",
    "device_id": "3bafab7b-4400-4bcf-8e6e-09f954699940",
    "type": "sale",
    "status": "requested",
    "amount_minor": 0,
    "currency": "string",
    "reference": "string",
    "terminal_serial": "string",
    "uti": "string",
    "auth_code": "string",
    "response_code": "string",
    "rrn": "string",
    "card_scheme": "string",
    "masked_pan": "string",
    "entry_mode": "string",
    "error_message": "string",
    "created_at": "string",
    "completed_at": "string"
  }
}

{
  "error": "string",
  "message": "string",
  "code": "string"
}

{
  "error": "string",
  "message": "string",
  "code": "string"
}

{
  "error": "string",
  "message": "string",
  "code": "string"
}

{
  "error": "string",
  "message": "string",
  "code": "string"
}

{
  "error": "string",
  "message": "string",
  "code": "string"
}