In Finland, a payment term between businesses can be longer than 30 days only if it has been expressly agreed. From 1 July to 31 December 2026, late payment interest is 10.5% in commercial contracts and 9.5% in other cases, because the reference rate under the Interest Act (korkolaki) is 2.5%. On an overdue business invoice you can also claim a fixed €40 compensation for recovery costs. This article explains where those numbers come from and how to put them on an invoice.

How long a payment term can you give another business?

The rule is 30 days. A longer payment term is valid only if the parties have expressly agreed on it.

The rule is in section 5 of the Act on Payment Terms in Commercial Contracts (maksuaikalaki, 30/2013). The act does not set a fixed upper limit for business-to-business terms. Instead, a term that is unreasonable to the supplier can be adjusted under section 9.

"Expressly agreed" means agreed separately, not a 60-day term buried in the buyer's standard purchase terms.

When the debtor is a public contracting entity (hankintayksikkö), such as a municipality or a government agency, the term is at most 30 days. It can be extended to at most 60 days, and only by express agreement (section 4).

What is the late payment interest rate in Finland in 2026?

Late payment interest is calculated from the reference rate under the Interest Act, which the Bank of Finland (Suomen Pankki) confirms twice a year. From 1 July to 31 December 2026, the reference rate is 2.5%.

The higher commercial rate (section 4 a of the Interest Act) applies to invoices between businesses and to invoices where a public entity is the debtor. Consumer claims use the general rate, and a contract cannot set terms that are worse for the consumer.

Because the reference rate changes every six months, on 1 January and 1 July, word the interest on your invoice template as "late payment interest according to the Interest Act", or check the percentage at the start of every period. The next change is due on 1 January 2027.

How do you calculate late payment interest to the day?

Late payment interest runs on the overdue amount for each day the invoice is late, from the due date until the day it is paid.

Example. A company invoices another company €5,000. The invoice is due on 15 July 2026 and the customer pays on 29 September 2026, 76 days late. The whole delay falls in the period when the commercial rate is 10.5%.

The interest is €5,000 × 10.5% × 76 / 365 = €109.32.

Add the €40 fixed compensation, and the late payment costs the customer €149.32.

Interest is always calculated at the rate in force for each day. The rate periods change on 1 January and 1 July, so if a delay runs across the change, the interest is calculated in two parts.

What is the €40 fixed compensation?

The fixed compensation (vakiokorvaus) is a flat amount for recovery costs that a creditor can claim from a business debtor without showing what the costs actually were.

It comes from the same Act on Payment Terms in Commercial Contracts. The right to it arises when the right to late payment interest arises, which means as soon as the payment is late.

Three things are worth knowing:

• It applies only to claims between businesses and against public entities, never to consumer claims.

• It arises separately for each overdue invoice, so five late invoices mean five compensations.

• It needs no separate collection step. You can claim it directly in your first payment reminder (maksumuistutus).

Which payment terms should a small company avoid?

Three common terms cause a small supplier more trouble than the sales they bring in:

• The term starts when the buyer approves the invoice, not from the invoice date. The buyer decides when the clock starts.

• A set-off clause lets the buyer deduct its own claims from your invoice without a separate agreement, which hands the buyer every dispute.

• Pay when paid ties your payment to the buyer's own customer paying them, so you carry the risk of a deal you are not a party to.

None of these is automatically invalid, and an unreasonable term can be challenged. The easier route is to check, at the quote stage, which purchase terms the contract refers to.

How do you write the payment term on the invoice?

A payment term is not a mandatory particular under the VAT Act, but it is a contract term that binds both parties.

A clear wording has three parts: the payment term in days, the due date as a date, and the basis for late interest. For example: "Payment term 14 days net. Due date 13 October 2026. Late payment interest according to the Interest Act."

A due date alone usually works, but it does not show from which day the term started. If the invoice went out late, that difference can matter.

Everything else the invoice has to show is listed in our article on what an invoice needs to include in Finland.

Is a short payment term worth it?

A short payment term improves cash flow, but only if customers keep to it. For a small company, 14 days is a normal starting point, and the 30-day rule is on your side when a large buyer pushes for longer.

What actually speeds up payment is rarely a stricter term. It is sending the invoice the day the work is done, to the right person, with a reference number (viitenumero) so the payment is matched automatically. When a customer still pays late, the next step is a written payment reminder.

Frequently asked questions

What is the late payment interest rate in Finland in 2026?

From 1 July to 31 December 2026, the general rate is 9.5% and the rate in commercial contracts is 10.5%. The reference rate for the same period is 2.5%.

How long can a payment term between businesses be in Finland?

A term longer than 30 days is valid only if it has been expressly agreed. There is no fixed upper limit, but an unreasonable term can be adjusted.

Can I charge late payment interest if it is not on the invoice?

Yes. The right comes from the law, not from the invoice. Stating it simply prevents disputes.

Can I claim the €40 compensation from a consumer?

No. The fixed compensation applies only to claims between businesses and against public entities.

When does late payment interest start to run?

From the due date. Interest accrues for each day until the invoice is paid.

Why is a payment term a cash flow decision?

Your payment term decides how long your company finances your customers' business with its own cash. The difference between 14 and 45 days is a month of working capital, and a small company feels it straight away.

NoCFO is the all-in-one AI-native finance platform for entrepreneurs and founders. With invoicing and bookkeeping on the same platform, open receivables are visible without a separate tracking spreadsheet. The platform does the routine work and you or your accountant stay in control: NoCFO suggests, a person reviews and approves.

For the whole picture, read our guide to invoicing in Finland. To see what your customers owe you today, start free at nocfo.io.

Sources (checked 29 September 2026)

• Suomen Pankki via STT: Korkolain mukainen viitekorko ja viivästyskorot 1.7.–31.12.2026 (reference rate 2.5%, late payment interest 9.5% and 10.5%)

• Finlex: Laki kaupallisten sopimusten maksuehdoista 30/2013 (payment terms between businesses and for public entities, adjustment of unreasonable terms, €40 fixed compensation)