Preguntes Freqüents - FAQ

WHMCS supports 100+ payment gateways out of the box, but most resellers do fine with a small set: Stripe, PayPal, and a manual-payment option. This article covers what to enable, how to set each up, and the trade-offs that matter for a small hosting business.

Recommended starter set

1. Stripe — takes credit cards on a hosted page. Lowest friction for most customers. ~2.9% + 30 cents per transaction.
2. PayPal — covers customers who don't want to share card details with a new vendor. Some customers will only pay via PayPal. ~3.49% + 49 cents per transaction.
3. Mail-in Payment — for the rare customer who wants to send a check. Free but slow. Often required for B2B customers with procurement processes.

Skip the others until a customer specifically asks. Adding gateways isn't free of friction — each one is a checkout-page option you'll need to maintain.

Setting up Stripe

1. Sign up at stripe.com and complete the business verification.
2. Go to your Stripe dashboard → Developers → API keys.
3. Copy the Publishable key and Secret key. Use the live keys, not test keys.
4. In WHMCS → System Settings → Payment Gateways, find Stripe and click Activate.
5. Paste the keys.
6. Set Display Name to "Credit Card" — your customers don't need to know the underlying processor.
7. Save.

Configure Stripe webhooks

Webhooks let Stripe notify WHMCS of payment events asynchronously (subscription renewals, refunds, disputed charges). Without webhooks, recurring billing is unreliable.

1. Stripe dashboard → Developers → Webhooks → Add endpoint.
2. Endpoint URL: https://yourbillingdomain.com/modules/gateways/callback/stripe.php
3. Events to send: select all charge.*, customer.subscription.*, and invoice.*.
4. Save the endpoint signing secret and paste it back into the WHMCS Stripe settings under "Webhook Secret."

Setting up PayPal

PayPal has multiple integration methods. WHMCS supports two:

PayPal Smart Buttons (recommended)

1. Sign up at developer.paypal.com and create a REST API app.
2. Copy the Client ID and Secret from the app dashboard.
3. WHMCS → Payment Gateways → PayPal Smart Buttons → Activate.
4. Paste the credentials.
5. Save.

This shows a "Pay with PayPal" button on checkout. Customers can use a PayPal account or pay-with-card-without-account.

PayPal IPN (legacy)

The older method, still supported. Requires:

• PayPal account email
• IPN URL configured in PayPal: https://yourbillingdomain.com/modules/gateways/callback/paypal.php

Use Smart Buttons unless you have a specific reason for IPN.

Setting up Mail-in Payment

1. WHMCS → Payment Gateways → Mail-in Payment → Activate.
2. Paste payment instructions: where to send the check, who to make it out to, what to write in the memo line.
3. Save.

Customers selecting this option get an unpaid invoice. You manually mark it Paid when the check clears.

Other gateways worth knowing about

• Authorize.net — the "established" credit card gateway. Higher monthly fees ($25/mo) but lower per-transaction fees if you do high volume. Good for established hosts.
• 2Checkout / Verifone — merchant of record service that handles VAT, sales tax, and chargebacks for you. Higher fees (~5%) but eliminates compliance burden for international sales.
• Crypto.com Pay, Coinbase Commerce, BitPay — cryptocurrency payment gateways. Niche but appreciated by some customer segments.
• GoCardless — direct debit (ACH in the US, BACS in the UK). Cheaper than cards (~1%) but slower.

Currency considerations

If you sell in multiple currencies:

1. Set up additional currencies in WHMCS → System Settings → Currencies.
2. Set exchange rates manually or enable automatic updates from WHMCS's currency feed.
3. Each gateway only supports specific currencies — verify before announcing support to customers.

Most US-based resellers stick to USD for simplicity. International expansion is a separate project.

Handling failed payments

WHMCS automatically retries failed credit card payments per its retry schedule (configurable in Automation Settings). Default: retry on day 3, 5, and 7 after due date, then suspend on day 7-14.

For accounts with chronic payment failures (declined cards, expired cards), the customer needs to update payment details. WHMCS sends automated emails for this; the email template is editable.

PCI scope considerations

Both Stripe and PayPal Smart Buttons keep card data off your server entirely (Pattern A in our PCI compliance article). Your PCI obligations are the simplest possible (SAQ A).

Avoid gateway integrations that ask you to enter or store the customer's card number on your server — that pulls you into a much harder PCI scope.

Common pitfalls

• Test mode in production. Easy to forget you're still using test API keys. Confirm by trying a small real transaction after going live.
• Webhook URLs not whitelisted. If you use a firewall or Cloudflare, make sure Stripe and PayPal can reach your WHMCS webhook endpoints.
• Currency mismatch. Customer in EUR, gateway processes in USD. Customer sees "currency conversion fee" on their card statement and chargebacks.
• Missed renewals. Cron isn't running, or the gateway's recurring billing isn't configured. Test by setting up a one-month subscription and waiting for the renewal.