Payzum is a non-custodial crypto payment gateway for WHMCS. Your clients pay invoices in USDC, USDT and other supported coins; funds go directly to your wallet, with no chargebacks.

How it works

• The client clicks Pay on a WHMCS invoice and lands on a hosted Payzum checkout.
• They pick the coin and network from the accepted-tokens list you configure.
• A signed webhook (HMAC-SHA-512, 10-minute replay window) marks the invoice paid in WHMCS.

Features

• Hosted checkout; the buyer chooses the coin (multi-chain).
• Exact decimal amounts end to end.
• Duplicate protection: one Payzum invoice per WHMCS invoice, reused while it is open.
• Amount and currency are verified against the invoice before crediting.
• Native WHMCS settlement (addInvoicePayment), overpayments covered.
• Production and staging environments selectable in the gateway settings.
• Payzum fee recorded as the transaction fee, so WHMCS matches your wallet.

Pricing

The module is free. Payzum charges 0.5% per processed sale, deducted from the amount received, plus on-chain network gas.

Requirements

PHP 8.1+ with cURL. Needs a Payzum merchant account (API key + webhook secret): https://payzum.com Docs and integration guide: https://payzum.com/integration/ Source (MIT): https://github.com/payzum-dev/whmcs-payzum