> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zbx.boomfi.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# WHMCS

> Offer crypto checkout in WHMCS with one-time and recurring pay links.

Integrate ZBX with [WHMCS](https://www.whmcs.com/) so clients can pay invoices with cryptocurrency at checkout.

<Warning>
  **Single-item checkout only.** Multi-item carts are not supported for the crypto payment method. Customers see an error on multi-line invoices if the crypto method is selected.
</Warning>

## Setup

### 1. Merchant account

Create and KYB-ready your organisation at [https://merchants.zbx.boomfi.xyz/](https://merchants.zbx.boomfi.xyz/).

### 2. API key

1. Open `https://merchants.zbx.boomfi.xyz/dashboard/settings/api-keys`
2. **Create API key**, name it, store the secret

### 3. Pay links

Create:

* One **one-time** pay link (enable **allow repeat payments without confirmation** so multiple checkouts can reuse it)
* One **recurring** pay link for subscription-style billing

See [Payment Links](/payments/paylinks).

### 4. Install and configure the WHMCS module

1. In WHMCS, open **Apps & Integrations**.
2. Search for the crypto payment module and activate it.
3. Configure:

| Field                  | Purpose                                                                      |
| ---------------------- | ---------------------------------------------------------------------------- |
| Show on order form     | Whether crypto appears at checkout                                           |
| Display name           | Label clients see (for example “Crypto payment”)                             |
| Test mode              | Use pay links / keys from a separate test merchant account when you have one |
| One-time payment link  | From step 3                                                                  |
| Recurring payment link | From step 3                                                                  |
| API key                | From step 2                                                                  |

## Test mode

Enable **Test mode** in WHMCS only if you have a separate test merchant account. Use that account's pay links and API keys.

## Live mode

Disable test mode and use production pay links and API keys from [https://merchants.zbx.boomfi.xyz/](https://merchants.zbx.boomfi.xyz/).

## Related

* [Integrations Overview](/integrations/overview)
* [Payment Links](/payments/paylinks)
* [Subscriptions](/payments/subscriptions)