Set up automatic invoicing with Onfact

What happens automatically

After a buyer completes payment:

1. bookto checkout confirms the payment via Mollie.
2. bookto sends the order details to Onfact using your API credentials.
3. Onfact creates the invoice as a concept — not yet sent, not yet finalised.
4. The Onfact invoice number is written back to your bookto order so you can match them.

The invoice contains the buyer's name, email, the product name and price, and the correct VAT treatment based on the buyer's country and VAT status.

What you do yourself

Onfact creates the invoice, but it does not send it. That is intentional — you stay in control. In Onfact:

1. Go to Invoices and find the new concept invoice.
2. Review it — check the buyer details, the amount, and the VAT line.
3. Adjust if needed (for example, if the buyer provided a VAT number for a business purchase).
4. Click Send to deliver the invoice to the buyer by email.

VAT on seller-to-buyer invoices

The VAT treatment depends on the buyer's situation:

• Belgian buyer, no VAT number — standard Belgian VAT applies (rate depends on your product category).
• EU buyer with a valid VAT number — reverse charge applies. The invoice shows €0 VAT with the note BTW verlegd / Reverse charge — art. 44 of the VAT Directive. The buyer accounts for the VAT in their own country.
• EU buyer without a VAT number — standard VAT applies based on the buyer's country (OSS rules).

Onfact handles this automatically based on the data bookto sends. If you are unsure about your VAT obligations as a seller, consult your accountant.

If no invoice appears in Onfact

1. Check whether the order is a test order — Onfact invoicing is blocked for test orders by design. Use a live payment (even €0.01) to test the integration.
2. Verify that your API key and UUID in bookto Integrations are still valid.
3. If that doesn't solve it, contact support@bookto.eu with the order number — we can check the logs for you.