Register payment
Register a received payment, full or partial, against a customer invoice.
POST https://cotlet.dev/api/v1/fortnox/invoices/{invoice_number}/payments
write Confirm
Registers a payment on one customer invoice with the amount and the payment date you give, like Registrera inbetalning in Fortnox. A partial payment leaves the invoice open for the rest; a payment that covers the balance marks it as fully paid. Read the balance with get_invoice first. By default you confirm each call; you can switch that off for this tool.
Parameters
| Name | Type | Description |
|---|---|---|
| invoice_number string required | string | Invoice number from list_invoices or create_invoice. |
| amount number required | number | Amount received, in the invoice currency. |
| payment_date date | date | Date the money arrived. Default: today. |
Request
curl -X POST https://cotlet.dev/api/v1/fortnox/invoices/2377/payments \
-H "Authorization: Bearer $COTLET_API_KEY" \
-H "Content-Type: application/json" \
-d '{"amount":15000,"payment_date":"2026-10-13"}'result = client.call("fortnox", "register_payment", {"invoice_number":"2377","amount":15000,"payment_date":"2026-10-13"})const result = await cotlet.call('fortnox', 'register_payment', {"invoice_number":"2377","amount":15000,"payment_date":"2026-10-13"});cotlet call fortnox register_payment --data '{"invoice_number":"2377","amount":15000,"payment_date":"2026-10-13"}'Example response
{
"invoice_number": "2377",
"paid_amount": 15000,
"payment_date": "2026-10-13",
"balance": 0,
"status": "fully paid",
"currency": "SEK"
}