> ## Documentation Index
> Fetch the complete documentation index at: https://nayax-44d6e37b-fis-cortina.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> FisCortina is Nayax's fiscal reporting platform for integrators.

FisCortina is Nayax's fiscalization platform: a REST API that allows integrators to report transactions to regional tax authorities in real time. Rather than managing separate compliance implementations per country, FisCortina gives merchants a single solution covering payment processing and fiscal reporting together, regardless of the underlying regional regulation.

## Architecture

**Nayax calls your server.** Nayax sends fiscal requests to your endpoints. Your server communicates with the tax authority and returns a structured response, which Nayax relays back to the device. You implement the API; Nayax drives the calls.

The following components are involved in a FisCortina integration:

| Component            | Role                                                                       |
| -------------------- | -------------------------------------------------------------------------- |
| **Nayax Device**     | POS terminal that initiates payment and receives fiscal confirmation       |
| **Nayax Engine**     | Backend that processes payments and orchestrates fiscal calls              |
| **3rd Party Server** | Your server, which implements the FisCortina endpoints                     |
| **Tax Authority**    | Regional government system that receives and confirms fiscal registrations |

## Security

All FisCortina communication requires the following across both sandbox and production environments:

* **HTTPS with TLS 1.2 or higher** for all requests and responses
* **JSON** as the content format for both request and response bodies

## API Endpoints

FisCortina exposes three endpoints, all using `POST` with `application/json`:

| Method | Endpoint                                                     | Description                                                                                                                                        |
| ------ | ------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| `POST` | [/FisCortina/StartSession](/docs/fis-cortina/authentication) | Challenge-response authentication. Must be called before any transaction in a session. Returns `TranIDCipher`.                                     |
| `POST` | [/FisCortina/Register](/docs/fis-cortina/register)           | Registers a transaction with the tax authority. Triggered after Sale approval or Settlement, depending on configuration.                           |
| `POST` | [/FisCortina/Void](/docs/fis-cortina/void)                   | Un-registers a fiscal registration following a transaction void or cancellation. Echoes `FiscalId` and `FiscalRrn` from the original registration. |

<Warning>
  **Refund not yet supported.** The `/FisCortina/Refund` endpoint is not available. Do not implement or trigger refund calls in your integration at this time.
</Warning>

## Next steps

<CardGroup cols={2}>
  <Card title="Integration Lifecycle" href="/docs/fis-cortina/integration-lifecycle">
    Follow the full onboarding process from kickoff to production launch.
  </Card>

  <Card title="Authentication" href="/docs/fis-cortina/authentication">
    Implement the StartSession challenge-response before sending fiscal requests.
  </Card>
</CardGroup>