Accept Card Payments in WHMCS — Powered by Paddle Billing

Let your customers pay invoices and set up automatic renewals through your Paddle account. Cards, PayPal, Apple Pay and Google Pay are handled in an overlay checkout without leaving your client area, and Paddle acts as Merchant of Record so sales tax and VAT are calculated, collected and remitted for you.

No addon module, no database setup, no cron entry. Enter your Paddle API key, client-side token and webhook secret, and the module handles everything else.

Features

• Fully Automatic Setup — Enter your Paddle credentials; the module creates everything it needs on first use.
• One-Time and Recurring Payments — Take a single payment for an invoice, or set up automatic renewals that charge the card each cycle. Both options are offered on the invoice — you choose which leads, or restrict the gateway to one-time payments only.
• Six Billing Cycles — Monthly, quarterly, semi-annual, annual, biennial and triennial, for hosting services and product addons alike.
• Client-Managed Billing — Clients see their card on file and next payment date on their service page, and can replace an expiring card or switch off automatic billing themselves — without opening a ticket.
• Secure Card Replacement — Card details are entered on Paddle's own pages. Card numbers never reach your server and are never stored in WHMCS.
• Expiry Warnings — Clients are warned on their service page when the card on file will expire before their next payment is due, which is the cheapest moment to fix it.
• Overlay Checkout — Customers pay in a modal on your invoice page. Cards, PayPal, Apple Pay, Google Pay and local methods are all supported by Paddle.
• Sales Tax & VAT Handling — Paddle calculates and remits tax for the customer's jurisdiction as Merchant of Record. Configure the module to match your Paddle account, and optionally display a notice at checkout so customers are never surprised by the amount.
• Full & Partial Refunds — Issue refunds straight from the WHMCS invoice page; refund status updates from Paddle are recorded in the gateway log.
• Automatic Cancellation — Terminating a service or addon cancels its Paddle subscription automatically, so nobody keeps being charged for a service they no longer have.
• Multi-Currency — Charges in the client's own currency, including zero-decimal currencies such as JPY, KRW and VND.
• Invoices of Any Shape — Setup fees, promotional discounts, addons and multi-item invoices are all handled correctly, and renewals charge the service's own recurring price.
• Renewal Dates That Hold — Automatic renewals are charged against the service's existing due date, so a client who pays late does not drift into repeating late fees and suspensions.
• Late Fee Control — Choose whether a late fee is waived when a delayed automatic payment finally succeeds, or left for the client to settle.
• Daily Self-Check — An optional daily check runs on your existing WHMCS cron and emails your administrators if the integration needs attention. It sends nothing when everything is healthy.
• Sandbox Mode — Test the entire flow against Paddle's sandbox before taking real money.

How It Works

1. Customer opens their WHMCS invoice and chooses Subscribe or Pay Now
2. Paddle's checkout opens over the invoice page
3. Customer enters card details; Paddle calculates any applicable tax before payment
4. Payment is captured and the invoice is marked Paid automatically
5. Future renewals are charged on the service's own due date, with no action from you

Requirements

• WHMCS 9.0
• PHP 8.2 or later with cURL extension
• HTTPS on your WHMCS installation
• Paddle Billing account (Paddle Classic is not supported)
• A default payment link configured in your Paddle account

Installation

1. Upload module files to your WHMCS installation directory
2. Go to Configuration → Payments → Payment Gateways
3. Activate Paddle Billing v26.8
4. Enter your Paddle API Key, Client-Side Token and Webhook Secret
5. Add a notification destination in Paddle pointing to the module's callback URL (the included README lists the exact events)
6. Save — customers can now pay by card

Security

• Card data never touches your server — all card entry happens on Paddle's pages
• Every incoming notification is signature-verified before it is processed
• Notifications are rejected outright if no webhook secret is configured
• Payments are recorded exactly once, however many notifications arrive

PHP

Works on PHP 8.2 and 8.3 — the versions WHMCS 9.0 itself supports. The module code is additionally verified on PHP 8.1 and 8.4, so it will not be the blocker when WHMCS adds newer PHP support.

Support

Website: https://www.aheadhostllc.com Developed by Ahead Host LLC