Finnish reference number calculator (viitenumero)

Yes. The invoicer forms the reference number, for example from an invoice or customer number. The base has 3 to 19 digits, and a check digit is always added at the end; the calculator adds it for you.

You make it yourself: choose a base, such as the invoice number, and add the check digit with this calculator. Our invoice template builds the reference number from the invoice number automatically.

Leading zeros are not printed. They do not change the check digit either, so leave them out: 0001234561 is written 12 34561.

At least 4 digits (3 plus the check digit) and at most 20 (19 plus the check digit). Short is better, because the payer is less likely to mistype it.

The international creditor reference (ISO 11649), which also works on domestic invoices. It starts with RF and two check digits, followed by up to 21 characters. Since 18.11.2024 it no longer has to be built from a Finnish reference number.

The invoice entries required by the Finnish VAT Act do not include one. A reference number does let the payment match the right invoice automatically, and a bank barcode can only be made for an invoice with a reference.

It does not have to be. It is often the invoice number plus a check digit. For recurring payments such as rent, Finance Finland advises leaving the instalment number out of the reference, because a payment usually settles the oldest amount owed.

No. The payer must use the reference exactly as it appears on the invoice and must not convert a Finnish reference into an RF reference or the other way round.

Reference number, or Finnish reference number; the RF version is the RF creditor reference. The other Finnish invoice terms are in our article Finnish invoice terms in English.