The "Custom" Payment Gateway

The Custom gateway is intended for manual payment methods such as bank transfers, cash, checks, or any other offline workflow you handle yourself.

Note

Want to integrate with an external payment processor like Stripe? See the Creating a Payment Gateway guide instead.

How It Works

1. Client selects "Custom" at checkout
2. FOSSBilling displays your configured instructions
3. Client follows the instructions to pay you
4. You receive the payment
5. You manually mark the invoice as paid in FOSSBilling

Configuration

Go to Configuration → Payment gateways → Custom.

Two template fields:

• Single payment information — For one-time payments
• Subscription information — For recurring payments (if supported)

Both support Twig templates and HTML.

Caution

Only trusted administrators should edit these templates. The content renders in the client area, so malicious JavaScript could compromise your customers.

Never paste untrusted code or scripts from unknown sources.

Available Variables

Variable	Type	Description
invoice	array	Full invoice data: total, currency, line items, buyer info
_client_id	int	ID of the paying client

Example Templates

Bank Transfer Instructions

<div style="padding: 20px; border: 1px solid #ddd; border-radius: 8px;">
    <h3>Bank Transfer Instructions</h3>
    <p>Please transfer the following amount to our bank account:</p>
    <ul>
        <li><strong>Amount:</strong> {{ invoice.total }} {{ invoice.currency }}</li>
        <li><strong>Reference:</strong> {{ invoice.serie_nr }}</li>
        <li><strong>Bank:</strong> Example Bank</li>
        <li><strong>IBAN:</strong> GB00 XXXX 0000 0000 0000 00</li>
        <li><strong>BIC/SWIFT:</strong> EXAMPLEXX</li>
    </ul>
    <p>Your invoice will be marked as paid once we confirm the transfer (1-3 business days).</p>
</div>

Conditional by Currency

Show different instructions based on invoice currency:

% if invoice.currency == 'EUR' %
    <p>Transfer to: DE00 0000 0000 0000 0000 00</p>
% elseif invoice.currency == 'USD' %
    <p>Transfer to: 1234567890 (Routing: 021000021)</p>
% else %
    <p>Contact support for {{ invoice.currency }} payment instructions.</p>
% endif %

Wrap the above with the standard Twig delimiter characters ({ and }) when using in your template.

Debugging

To see all available data in the invoice variable, temporarily enable debug mode and add this to your template:

<pre>
{{ dump(invoice) }}
</pre>

Remember to disable debug mode when you're done!

Marking Invoices as Paid

After receiving payment:

1. Go to Invoicing → Invoices
2. Find the invoice
3. Click "Mark as paid"
4. The system activates services and emails the client

Source Code

The Custom adapter is at src/library/Payment/Adapter/Custom.php. It's a simple example of how payment adapters work.