The NETbilling payment gateway module is available in WHMCS.
The Netregistry Pay payment gateway module is available in WHMCS.
The NoChex payment gateway module is available in WHMCS.
Use Offline Credit Card with your own processor for offline payments.
The Optimal Payments payment gateway module is available in WHMCS.
The PagSeguro payment gateway module is available in WHMCS.
The Pay Junction payment gateway module is available in WHMCS.