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

# Payment Sources

> Store reusable card token references for recurring billing.

# Payment Sources

## In a nutshell

Payment sources let the engine charge future subscription renewals without asking the customer to enter card details every billing cycle.

## Card payment sources

The card flow works like this:

1. The customer pays through Nomba Checkout.
2. Checkout tokenization returns a reusable `tokenKey`.
3. The engine stores the token as a card payment source.
4. Future renewals charge the saved token.

## Card metadata

A saved card payment source can include:

| Field                | Description                              |
| -------------------- | ---------------------------------------- |
| `last4Digits`        | Last four card digits.                   |
| `type`               | Card type.                               |
| `currency`           | Card currency.                           |
| `expiryMonth`        | Expiry month.                            |
| `expiryYear`         | Expiry year.                             |
| `authorizationToken` | Nomba token key used for future charges. |

<Warning>
  Never collect or store full card details in your application. Use hosted checkout and tokenized card references.
</Warning>

## API availability

Payment sources are created from successful tokenized checkout payments. Public payment source management endpoints are not currently exposed.