Overdue invoices in Finland: reminders, interest and debt collection

You have finished the job and sent the invoice, but the payment deadline has passed and the money has not arrived. Start by checking that the client received the correct invoice and that their payment has not simply been allocated to the wrong reference. Then contact them and agree on what happens next.

In Finland, the rules for reminder fees and debt collection depend on whether the client bought the service for personal use or for their business. If you use an invoicing service, coordinate your reminders with the company that issued the invoice so that the client receives one consistent set of instructions.

This guide covers ordinary invoices for work and services in Finland. It includes a reminder email you can adapt and an example of how to calculate interest on a late payment.

For a quick overview first, read the six steps to collecting an unpaid invoice, from your first reminder to a collection agency and, if necessary, court and enforcement.

Contents

1. Check the invoice and payments first
2. Is the client a consumer or a business?
3. When can you send a payment reminder?
4. A reminder email with no additional fee
5. Calculating interest on late payments
6. The EUR 40 compensation for commercial payments
7. Agreeing a payment plan or using a collection agency
8. What if the client disputes the invoice?
9. Following up an invoice issued through Bisse
10. Making the next invoice easier to collect

1. Check the invoice and payments first

An overdue invoice may be the result of a forgotten payment, a missing purchase order number or an incorrect billing address. Before you follow up, check:

• whether the invoice was sent to the agreed email address or e-invoicing address
• whether the amount and payment terms match the agreement
• whether the client needs a project reference or approval from a particular person
• whether a payment has arrived with the wrong reference, or only part of the invoice has been paid
• whether the client has already reported an error or raised a complaint about the work

If the client says they have paid, ask for the payment date and reference so the transaction can be traced. If they never received the invoice, resend the original to the right address and discuss the payment deadline if necessary. Creating another sales invoice for the same work can result in duplicate billing.

For business clients, confirm the e-invoicing address and any purchase order reference before you start the job. Our guide to e-invoicing in Finland explains the details you will need.

2. Is the client a consumer or a business?

Someone booking a cleaner for their home will usually be a consumer. Someone booking the same service for their company’s office is a business client. The purpose of the purchase matters: a person with a Finnish Business ID can still buy a service privately.

* If the creditor cannot deduct VAT, an amount corresponding to VAT may be added to the statutory cost limit for collecting a business debt.

You can charge reminder costs only when the relevant timing requirements and other conditions are met. These figures are maximum amounts; collection costs must also be reasonable. See sections 10 a, 10 e and 10 i of Finland’s Debt Collection Act (in Finnish). The interest rates come from the Bank of Finland’s notice for 1 July–31 December 2026 (in Finnish).

3. When can you send a payment reminder?

Once an invoice is overdue, you can begin with a polite reminder without charging a reminder fee. Identify the invoice, state the unpaid amount and explain how the client can pay or raise a query.

Charging for a consumer reminder

For the first reminder fee to be chargeable, the original invoice must have been sent at least 14 days before its due date, and at least 14 days must have elapsed after that date. If payment was agreed for a fixed date without a separate invoice, you must still wait at least 14 days after the due date before sending a reminder that carries a fee.

There must also be at least 14 days between successive reminders for which you charge. Under the Finnish Consumer Ombudsman’s interpretation, you exclude the due date or the previous letter’s sending date when counting that period: you cannot send the next letter on the 14th day itself.

The client must have enough time to respond after receiving the letter. KKV, the Finnish Competition and Consumer Authority, requires at least ten days, so allow for delivery time as well. Its decision on the timing of collection letters explains this interpretation (in Finnish).

Reminding a business client

The first reminder for a business debt does not have the same 14-day waiting period as a chargeable consumer reminder. You must still give the client a reasonable opportunity to pay and respond.

For a subsequent chargeable business reminder or payment demand, at least ten days must have elapsed since the previous reminder or demand was sent. This is a minimum interval between collection measures. The rule is in section 10 f of the Debt Collection Act (in Finnish).

4. A reminder email with no additional fee

Keep your message specific and straightforward. Replace the details in this example with those from your invoice:

Subject: Payment reminder for invoice 1042

Hello,

Invoice 1042 for EUR 1,000 was due on 1 October 2026. We have not yet received payment. The invoice covers the work completed and delivered in September as agreed.

This reminder, sent on 14 October 2026, carries no additional fee. Please pay the outstanding amount by 28 October 2026 using the bank account and payment reference on the attached invoice.

If you have already paid, please let us know the payment date and reference so we can trace it. If you have a question about the invoice or need to discuss a payment arrangement, please reply to this email.

Kind regards, Your name / the invoicing company

The example asks for the invoice balance only. If you also claim interest or other costs, itemise them, explain their basis and show the period used to calculate interest. Use the payment details of the company that issued the invoice. For a Bisse invoice, keep Bisse’s account details rather than substituting your personal account.

5. Calculating interest on late payments

Late payment interest compensates for the delay. It is an annual rate: a rate of 10.5% does not mean you immediately add 10.5% to every overdue invoice.

If the due date was fixed in advance in a way that binds the client, the Finnish Interest Act provides for interest from that date. Otherwise, interest generally starts only after 30 days have elapsed since the invoice or payment request was sent, and cannot run for a period before the client received it. In this latter situation, a consumer must also be told the interest rate and when it starts to apply. Putting a due date on an invoice therefore does not, by itself, settle the starting date in every case. See KKV’s guidance on payments and invoicing (in Finnish).

Example for a business invoice

Assume a business client owes EUR 1,000, including any VAT on the invoice. Interest accrues for 30 days during the second half of 2026, and the statutory commercial rate of 10.5% applies.

Interest = unpaid principal × annual rate × interest days / 365

This calculation excludes reminder fees, fixed compensation and collection agency charges. If the client makes a part payment, calculate interest for the remaining period on the reduced principal.

The Bank of Finland sets the statutory reference rate every six months. If a delay extends into another six-month period and the rate changes, split your calculation accordingly. The 9.5% and 10.5% rates used here apply only from 1 July to 31 December 2026.

6. The EUR 40 compensation for commercial payments

When a commercial payment is late and the creditor is entitled to late payment interest, the creditor may also be entitled to EUR 40 in fixed compensation for collection costs. This can apply, for example, to goods or services sold between businesses. It does not apply to consumer debts.

Other collection costs cannot simply be added in full on top of the EUR 40. You can recover them only to the extent that they exceed that amount. A EUR 12 reminder charge therefore does not turn the compensation into EUR 52.

In the example above, the amount claimed would be EUR 1,048.63 if the creditor also claims the EUR 40 compensation and the conditions are met. Show interest and compensation separately. The legal basis is section 10 i of the Debt Collection Act (in Finnish).

7. Agreeing a payment plan or using a collection agency

If the client accepts that the invoice is correct but cannot pay it all at once, a realistic payment plan may help you recover the money. Put the instalment amounts, dates, outstanding principal and treatment of interest in writing. Agree on what happens if an instalment is missed.

Ask for a specific date rather than accepting an open-ended promise to pay next week. If Bisse or a collection agency is handling the invoice, coordinate the arrangement with them.

Keep the contract and the client’s approval of the work

A written agreement and a record of the client’s acceptance make it easier to explain and substantiate an unpaid invoice. Before you start, agree on the scope, price, payment terms and when completed work or a project stage can be invoiced. Establish who approves the work and how that approval will be recorded.

When you deliver the work, ask for written confirmation, for example by email. For hourly work, a timesheet approved by the client helps establish the hours you can charge for. Keep approvals for additional work and any comments or outstanding corrections together with the original agreement. These records strengthen your evidence, but do not guarantee payment or resolve a dispute about defects on their own.

If you engage a collection agency, provide the accepted offer or contract, the client’s approval of the work, the invoice, reminders, payments received and relevant correspondence. Our guide to client contracts covers what to agree in advance.

When reminders do not lead to payment

For a consumer debt, a professional collector may issue a payment demand only after the overdue debt has been the subject of a reminder and at least 14 days have elapsed since that reminder was sent. A formal payment demand is a different document from your own reminder email. KKV explains the stages in its guide to the debt collection process.

Before instructing an agency, check what you will be charged and which costs can be claimed from the client. The agency’s price to you and the debtor’s liability are separate matters. Collection cannot guarantee recovery if the client has no money to pay.

For business debts, Finland also permits a procedure called tratta: a payment demand that carries the threat of publication or an entry in a credit information register. It requires a due, clear and undisputed debt and a prior reminder that meets the legal requirements. It cannot be used for consumer debts. See section 7 of the Debt Collection Act (in Finnish).

Court proceedings and enforcement

If collection without court proceedings does not succeed, the creditor can bring a debt claim before a district court. An undisputed claim may be handled through a simpler summary procedure. An ordinary service invoice will generally need a judgment before enforcement can begin; referring it to a collection agency does not itself start enforcement.

Consider the size of the debt, the client’s ability to pay and the potential court costs before proceeding. Oikeus.fi explains debt claims and enforcement.

8. What if the client disputes the invoice?

A complaint about the quality of the work, the agreed price or whether the work was ordered needs to be addressed. Ask the client to identify the amount they dispute and their reasons, then respond using the agreement and records of the work.

Collection under the Debt Collection Act must stop if the debtor disputes liability on grounds that could affect their obligation to pay. The Act allows an exception where no grounds are given or the grounds clearly cannot affect liability. Inform the invoicing service or collection agency about the complaint. The rule is in section 4 b of the Debt Collection Act (in Finnish).

If you agree on a price adjustment, record the settlement and arrange any credit note through the company that issued the invoice. If agreement is not possible, the dispute may need legal proceedings. The contract and the client’s approval help show what was agreed and delivered.

9. Following up an invoice issued through Bisse

When you invoice through Bisse.fi without your own Business ID, the client pays using Bisse’s payment details. Your pay will normally be processed once the client’s payment reaches Bisse. An overdue invoice is therefore not money already available in your personal account.

If the invoice remains unpaid, send Bisse’s customer service the invoice number, the agreed terms and details of any complaint. Check which reminders have been sent and agree on the next steps so payments, client messages and collection measures can be handled consistently.

If you speak to the client directly, pass on any promised payment date and other relevant information. Keep the original payment details and coordinate interest, charges, payment plans or credits before confirming them to the client.

If you invoice through your own sole-trader business, known in Finland as toiminimi, or a limited company, the receivable belongs in your business accounts. Keep your accountant informed about part payments, credit notes and the progress of collection. You can also explore Bisse.fi’s service for sole traders.

10. Making the next invoice easier to collect

Good payment management starts with the order. Confirm the client’s name, billing details, payment terms and the person who approves the work. Record additional work separately and get approval before carrying it out.

For a longer project, agree on invoicing as completed stages are accepted so the entire fee is not left until final delivery. Include those stages and payment dates in the contract. Review unpaid invoices regularly and record any payment promises.

When a payment is late, a clear reminder and an agreed next step make follow-up more useful than repeated messages without a specific request. For the consequences of unpaid debts for credit information, read our guide to payment default records in Finland.

Ready to invoice your work through Bisse? Explore our invoicing service, check the current prices or register with Bisse.fi.

Official sources

• Bank of Finland: statutory reference rate and late payment interest, 1 July–31 December 2026 (in Finnish)
• Finlex: Debt Collection Act, especially sections 4 b, 7 and 10 a–10 i (in Finnish)
• Finlex: Interest Act, especially sections 4, 4 a, 5, 6 and 12 (in Finnish)
• KKV: timing of collection letters and the time consumers must have to respond (in Finnish)
• KKV: payments and invoicing (in Finnish)
• KKV: debt collection process
• Oikeus.fi: debt matters

Published on 14 October 2026. The interest rates shown apply from 1 July to 31 December 2026. Check the Bank of Finland’s notice for rates applicable in the next six-month period.