For Nuvei to authenticate REST API 2.0 requests, the merchant must include its API key in the header:

Authentication: X-API-KEY: {your API key}

The Nuvei Integration Team provides the API key to the merchant.

Example POST /payments Request

POST  /payment-api/payments HTTPS/1.1 
Host: api.nuvei.com
Content-Type: application/json 
x-api-key: {your API key}

{
  "processingEntityId": "dbdaacd8-e2b8-4e80-81e7-736a3e241fd0",
  "transactionType": "Sale",
  "amount": 60,
  "currency": "EUR",
...
}