Cryptonly Crypto Payment Gateway

Let your clients pay FOSSBilling invoices in Bitcoin, USDT, USDC and other cryptocurrencies. They pay on Cryptonly's hosted checkout, and the invoice is marked paid automatically once the payment is confirmed on-chain.

Your prices and invoices stay in your usual currency. Cryptonly converts the amount due at the live rate when the client picks a coin, so you don't maintain crypto prices. New coins and networks you enable in your Cryptonly account appear at checkout without a module update.

Why Cryptonly

• No chargebacks. A confirmed crypto payment can't be reversed like a card payment.
• Simple pricing. 0.5% per transaction. No setup fee and no monthly fee.
• Start today. You can begin accepting payments without account verification.
• Partial payments handled. If a client sends less than the total, the amount received is added to their account credit and the next checkout asks only for the rest.
• Invoices keep their deadline. The payment link stays valid until the invoice due date, from 15 minutes up to 30 days.
• Test first. Test mode runs against the Cryptonly sandbox with testnet coins.

How it works

1. You issue a FOSSBilling invoice for 100 USD.
2. Your client opens the invoice and chooses Pay with Cryptonly.
3. Cryptonly shows the amount in the coin they pick, at the current rate.
4. The client pays on the Cryptonly checkout page.
5. Cryptonly sends a signed webhook to FOSSBilling.
6. FOSSBilling credits the payment and marks the invoice Paid.

Requirements

• FOSSBilling 0.8 or newer
• Your FOSSBilling site on a public HTTPS address
• A Cryptonly account with an API key and a webhook signing key

Setup

1. Extract the zip in your FOSSBilling root folder.
2. Open System → Payment Gateways → New Payment Gateway and install Cryptonly.
3. Paste your API key and webhook signing key, then turn on Enabled.

There's no webhook to configure in Cryptonly: the module sends its own callback address with every invoice.

Full setup guide: docs.cryptonly.net/integration/plugins/fossbilling

Questions? Contact our team or write to support@cryptonly.net.