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

# Payment Flows

The SDK supports multiple transaction flows to accommodate diverse use cases, from single-step payments to multi-step preauthorization and confirmation processes. This flexibility allows developers to choose the flow that best suits their application's requirements while maintaining security and reliability.

The available transaction flows are:

<CardGroup cols={3}>
  <Card icon="shield-halved" title="Payment with Pre-Authorization" href="/docs/integrate-pos-device/emv-core/payment-flows/payment-with-authorization">
    Preauthorize a transaction amount, then confirm it for settlement in a second step. Ideal for scenarios where the exact final amount is unknown (such as EV charging).
  </Card>

  <Card icon="repeat" title="Closed Loop Transaction" href="/docs/integrate-pos-device/emv-core/payment-flows/closed-loop-transaction">
    Process MIFARE card operations on your own application server using the card UID, without involving bank transactions.
  </Card>

  <Card icon="bolt" title="Single Step Payment" href="/docs/integrate-pos-device/emv-core/payment-flows/single-step-payment">
    Authorize and settle a transaction immediately in one operation, streamlining the payment process for fast, straightforward use cases.
  </Card>

  <Card icon="money-bill-transfer" title="Pre-Authorization with External Settlement" href="/docs/integrate-pos-device/emv-core/payment-flows/pre-authorization-with-external-settlement">
    Separate the authorization and settlement phases, letting a 3rd-party server handle final settlement through the Nayax API. Ideal for EV charging and similar variable-amount use cases.
  </Card>
</CardGroup>