How to invoice in Finland: a step-by-step guide for 2026

Published 3 October 2026

To make an invoice in Finland, write your details and your customer's, a running invoice number, the date, what you sold and the price, VAT if you are VAT-registered, the due date and your bank account. A reference number is not a required entry, but it matches payments to invoices automatically. Send the invoice as a PDF by email, for example, and keep it for at least six years. A business invoices under its business ID (Y-tunnus); without one, you can invoice as a light entrepreneur through an invoicing service.

Fill in every step below on our free invoice template, which works out the VAT, the reference number and the bank barcode.

1. Who can invoice: business ID or invoicing service

A sole trader business (toiminimi) can usually be set up free of charge by registering with the Tax Administration only, and it gets a business ID. It must be entered in the Trade Register if it has to file financial statements there under the Accounting Act, or if you live permanently outside the EEA. The VAT Act requires the ID on a VAT-registered seller's invoices, and a business in the Trade Register, prepayment register or employer register must show it on its letters and forms. A sole trader usually also registers for the prepayment register so that customers do not withhold tax from its invoices.

Without a business ID, you can invoice as a light entrepreneur (kevytyrittäjä) through an invoicing service. The customer pays the service, which pays you wages or work compensation (työkorvaus); you need the matching tax card. If your work compensation exceeds 20 000 euros in a calendar year, you become liable for VAT and get a business ID when you register. If the service invoices in its own name, it is the seller and pays the VAT on the whole amount. Our article on light entrepreneur or toiminimi compares the two. Planning to invoice with neither a business ID nor a service? Check the tax position first: it depends on your situation. The steps below are for invoicing under your own business ID.

2. Your details and your customer's

Write your name or business name, address and business ID, and the customer's name and address. Goods sold to a business in another EU country, and sales on which the customer pays the VAT under the reverse charge, also need the customer's VAT number. Add your IBAN. Our invoice template can remember your own details in your browser.

3. The invoice number

Every invoice needs a running identifier. The numbering must show whether an invoice is missing, and no two invoices in the same financial year may share a number. Several series are allowed, and so are letters. With an invoice number of three digits or more, such as 1001, our template builds the reference number from it; a reference has digits only, so any letters are left out.

4. Dates, the due date and late-payment interest

Show the invoice date and, if different, the date of delivery or of the service.

You agree the due date with your customer. With a business customer, a payment term over 30 days is allowed only if expressly agreed. Late-payment interest runs from a due date fixed in advance; between businesses it is 10.5 % a year from 1 July to 31 December 2026.

On a consumer invoice, state the late-payment interest rate and the date it runs from, for example "Late-payment interest 9.5 % from the due date" (the rate for July to December 2026). Otherwise no interest is owed for the time before the customer is told. To be able to charge for a payment reminder, send a consumer's invoice at least 14 days before the due date.

5. Lines, prices and VAT

Each line shows what you sold (the quantity and kind of goods, or the type and extent of the service), the unit price without VAT and the VAT rate. Below come the taxable amount and VAT by rate, and the total.

VAT rate	For example
25.5 %	most goods and services, such as bookkeeping and cleaning
13.5 %	food, restaurant meals, books, passenger transport, accommodation
10 %	newspapers and magazines

What goes where is in our article on VAT rates.

An invoice without VAT. If you are not VAT-registered, the invoice must not show VAT or a VAT rate; on our template, untick "I am in the VAT register". Registration is compulsory once turnover passes 20 000 euros in a calendar year, as our article on the VAT registration limit explains.

VAT 0 % and reverse charge. Goods sold to a business in another EU country, and services on which the buyer pays the VAT under the reverse charge, need a special note, worded as in our article on invoice requirements.

6. The reference number and the bank barcode

A reference number (viitenumero) is not among the entries the VAT Act requires, but a payment made with it matches the right invoice automatically. You can form it freely, for example from the invoice number. It has 4 to 20 digits, the last one a check digit, and is printed in groups of five. Our reference number calculator works out the check digit. The international RF reference, RF plus two check digits, works on domestic and cross-border invoices.

The bank barcode holds the account, amount, reference and due date. It may be printed only for a Finnish IBAN and needs a reference number, and the invoice can still be paid by typing the details in. Our template draws it, together with the virtual barcode.

7. Sending it: PDF or e-invoice

E-invoicing is not generally mandatory in Finland, so you can send a PDF by email. The exceptions: a business customer can require an e-invoice if your turnover for the financial year is over 10 000 euros, and state agencies accept only e-invoices. The right does not cover invoices to private individuals. A PDF is not an e-invoice, and our template makes PDF and paper invoices only. More in our article on e-invoicing.

8. Keep a copy, and correct mistakes with a new invoice

Keep every invoice for at least six years from the end of the calendar year in which its financial year ended. For a calendar-year business, that is the end of the year the invoice relates to. An electronic copy is fine if its content stays unchanged and it can be read and printed for the whole period; see our article on receipts and record keeping. To correct an invoice you sent, issue a new one that refers to the original, for example by its number. For intra-EU supplies of goods, distance sales and reverse-charge sales, the correcting invoice must contain all the details; a reference alone is not enough.

The simplified invoice up to 400 euros

When the total is 400 euros or less including VAT, it is enough to show the date, the seller's name and business ID, what was sold, and the VAT amount or the taxable amount by rate. Prices may include VAT if the VAT amount is shown. A simplified invoice cannot be used for intra-EU supplies of goods, distance sales, or sales on which the buyer pays the VAT in another EU country.

Once you have the details together, make the invoice on our free invoice template. When the invoices start to add up, booking your sales invoices and filing the VAT returns are part of our services.

Sources

Please note: this is general information about Finnish rules, not advice for your own situation, and the rules change. Ask us before you act on it.

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