Guides · · 5 min read

Late payment interest 2026: what an unpaid invoice owes you

Statutory late payment interest for the second half of 2026 is 11.75% a year. How to work it out, when the CZK 1,200 compensation applies, and how to collect.

A client is a month past the due date and you are wondering whether you are allowed to ask for something on top. You are — and it does not have to be written into the contract. Statutory late payment interest is yours automatically under Czech law, and on business-to-business claims you can also charge a flat-rate compensation of CZK 1,200 for the cost of chasing the money. Here is how much that adds up to and how to actually collect it.

How much the statutory interest is in 2026

The rate is set by Government Regulation No. 351/2013 Coll.: annual late payment interest equals the ČNB repo rate in force on the first day of the calendar half-year in which the default began, plus 8 percentage points. The rate is then fixed for the whole period of default — later moves in the repo rate do not change it.

  • Default starting on or after 1 July 2026: the repo rate is 3.75% (ČNB raised it with effect from 19 June 2026) → statutory interest of 11.75% a year.
  • Default that began in the first half of 2026: the repo rate on 1 January 2026 was 3.50% → statutory interest of 11.50% a year.

Current and historical repo rates are published on the ČNB website, together with the calculation method.

The formula, with an example

Interest starts running on the day after the due date and accrues for every day of delay:

interest = amount owed × annual rate × days late / 365

Say you issue an invoice for CZK 50,000 due on 10 July 2026 and the client pays 60 days late. The default began in the second half of 2026, so the rate is 11.75%:

50,000 × 0.1175 × 60 / 365 = CZK 966 in late payment interest. Add the flat-rate compensation of CZK 1,200 and you can ask for CZK 2,166 on top of the invoice itself.

💡 Worth remembering: late payment interest is not a fine or a penalty. It is the statutory price of the debtor using your money. Asking for it is entirely legitimate, and with habitually slow payers it changes behaviour: paying late stops being free.

Contractual interest versus the statutory rate

The statutory rate applies only where you have not agreed a different one. Contractual late payment interest can be higher or lower; in B2B contracts something like 0.05% per day (18.25% a year) is common. Be careful with punitive rates, though — a court can cut back interest it considers disproportionate. And if neither the contract nor the order says anything about interest at all, the statutory rate applies automatically, so you are never left with nothing.

The CZK 1,200 compensation: once per claim

Under § 3 of Government Regulation No. 351/2013 Coll., on obligations between businesses (and in dealings with public contracting authorities) you have a right to minimum compensation of CZK 1,200 for the costs of pursuing the claim — regardless of what the chase actually cost you, and separately for each claim. If a client is sitting on three of your invoices, that is CZK 3,600. It does not apply to consumers.

Two details people forget: tax and the limitation period

  • Interest you receive is taxable income. In daňová evidence (the Czech cash-basis records kept by sole traders) you tax it when the debtor actually pays it — the entitlement on its own does not create taxable income.
  • The claim becomes time-barred after three years. Under the Civil Code the period usually runs from the moment you could first have enforced the right, which for an invoice is normally its due date. So do not leave collection "for later": once the period has run, the debtor only has to raise the limitation objection in court and the claim is unenforceable.

What to do when a client does not pay

  1. A reminder shortly after the due date. A friendly e-mail resolves most cases — usually the invoice was forgotten, not refused.
  2. A second reminder with the numbers. State the amount owed, the interest accrued to date and the CZK 1,200 compensation. Suddenly the delay has a visible price tag.
  3. A pre-action demand (předžalobní výzva). Sent by registered post or datová schránka (the state-run data box), with a payment deadline. It is a precondition for being awarded your costs if the case does go to court.
  4. A payment order or a claim. For undisputed invoices, the electronic payment order is fast and relatively cheap; a lawyer can take over the collection, and for smaller amounts an out-of-court instalment agreement is often the pragmatic route.
⚠️ Keep the paper trail. To enforce a claim you need evidence: the invoice, proof that it was delivered, and the reminders you sent. You can only collect what you can document.

Your invoicing app can take most of the first two steps off your hands. Taxorio tracks due dates and flags overdue invoices, and you send the reminder by e-mail straight from the app. On the PRO plan you can switch on automatic reminders, which go out on a schedule you set. And because the invoice can be shared as a public web link, you can see when the client first opened it — a useful pointer before you send a reminder, although opening the link is not proof that the invoice was delivered or read. The whole reminder sequence is covered in Non-paying clients and reminders.

In short

On an unpaid invoice you are entitled by law to late payment interest — 11.75% a year for default that began in the second half of 2026 (repo rate 3.75% plus 8 percentage points) — and on B2B claims to CZK 1,200 of flat-rate compensation per claim. Interest accrues for every day past the due date, at a rate fixed by the half-year in which the default started. Above all, do not sit on it: three years passes faster than it sounds, and a prompt reminder with the interest already calculated settles most cases without a lawyer.

Taxorio scope: Taxorio provides invoicing and income/expense records for Czech sole traders. It is not full accounting or personalised tax advice. For an unsupported or unusual case, verify the treatment with a Czech accountant or tax adviser before filing.

Frequently asked questions

What is the statutory late payment interest rate in 2026?
For default that began in the second half of 2026 it is 11.75% a year (the ČNB repo rate of 3.75% in force on 1 July 2026 plus 8 percentage points); for default from the first half of 2026 it is 11.50%. The rate is fixed by the repo rate in force on the first day of the half-year in which the default began and does not change for as long as the default lasts.
Am I entitled to late payment interest even if the contract says nothing?
Yes. Statutory late payment interest belongs to the creditor automatically under the Civil Code and Government Regulation No. 351/2013 Coll. You may agree a different rate in the contract; without such an agreement, the statutory rate applies.
What is the CZK 1,200 flat-rate compensation?
It is the minimum compensation for the costs of pursuing a claim under § 3 of Government Regulation No. 351/2013 Coll. It applies to obligations between businesses (and towards public contracting authorities), it is due separately for each claim, and you do not have to prove what the collection actually cost you. It does not apply to consumers.
Do I have to pay tax on late payment interest I receive?
Yes — both late payment interest and contractual penalties are taxable income. A sole trader keeping daňová evidence (cash-basis records) taxes them at the moment the debtor actually pays; an entitlement the debtor has not settled is not taxed.
When does a claim from an invoice become time-barred?
The general limitation period is three years and normally runs from the moment you could first have enforced the right, which for an invoice is usually its due date. Once it has run, the debtor only has to raise the limitation objection in court and you can no longer enforce the claim, so do not delay collection.