Zahlungsverzug: Verzugszinsen, 40-Euro-Pauschale und Mahnung richtig nutzen

Customers pay late and you are left waiting. German law gives you clear tools: default interest, a 40 euro flat fee and a structured dunning process. We show you when default begins, what you may charge and how to book the receivable correctly.

When does default begin?

Default requires that the claim is due and that you have sent a reminder (Section 286 (1) BGB). A reminder is not needed in several cases, for example when a payment date is fixed by calendar (Section 286 (2) no. 1 BGB). If your invoice says "payable by 15 December 2026", the customer is in default at the end of that day without further notice.

Without a fixed date, the 30-day rule applies: the debtor is in default no later than 30 days after the claim is due and the invoice has been received (Section 286 (3) BGB). For consumers this only applies if the invoice specifically pointed out this consequence. Between businesses, the invoice is enough.

Default interest: 9 points above the base rate

Section 288 BGB sets the rate. For monetary debts it is five percentage points above the base rate (Section 288 (1) BGB). For claims for payment where no consumer is involved, it is nine percentage points (Section 288 (2) BGB). The Bundesbank adjusts the base rate under Section 247 BGB on 1 January and 1 July. Since 1 July 2026 it is 1.52 percent.

• B2B claims: 1.52 % plus 9 points, so 10.52 % per year.
• Claims against consumers: 1.52 % plus 5 points, so 6.52 % per year.

Example: an invoice of 5,950 euros gross stays unpaid for 30 days, and the customer is a business. Interest is 5,950 euros times 10.52 % times 30 divided by 365, about 51.45 euros. Interest runs from the day default begins until payment.

The 40 euro flat fee

If the debtor is not a consumer, you are also entitled to a flat fee of 40 euros (Section 288 (5) BGB). It applies once per claim, regardless of your actual effort. If you later incur higher recovery costs, for example for a lawyer, the flat fee is credited against them. A clause in your terms that excludes the fee is ineffective if grossly unfair (Section 288 (6) BGB).

How to send reminders properly

1. Payment reminder: friendly and short, with invoice number, amount and a new deadline. Many payments are simply forgotten.
2. First dunning letter: set a deadline of about seven to ten days and mention default interest and the 40 euro fee.
3. Final dunning letter: explicitly announce the court dunning procedure.
4. Court dunning procedure: you can apply online for a payment order at the central dunning court. If the debtor does not respond, an enforcement order follows.

Document every reminder with date and proof of receipt. It helps in a dispute.

Watch the statute of limitations

The regular limitation period is three years and starts at the end of the year in which the claim arose and you became aware of it (Sections 195, 199 BGB). An invoice from November 2026 therefore generally becomes time-barred on 31 December 2029. A payment order suspends the limitation period, a simple reminder does not.

Booking it correctly

Default interest you receive is interest income and belongs in your profit calculation. The 40 euro fee is generally damages and therefore not subject to VAT. It is still recorded as business income.

If a claim is finally lost, you correct VAT under Section 17 UStG: the VAT amount is reduced in the filing period in which the claim became uncollectible. Under accrual-basis VAT, this is how you recover the VAT you already paid.

Prevention beats dunning

• State a specific payment date on every invoice.
• Agree on deposits or shorter payment terms with new customers.
• Invoice promptly. Every delay also delays the payment.
• Review open items regularly and send reminders on a fixed schedule.

With a clean open-items list, you see immediately which customers are in default. If you outsource your bookkeeping to us, you receive this overview monthly with your report.