Guide · Payment reminders

How to write a payment reminder: default, deadlines, interest

When a customer does not pay, you remind them of the open invoice with a payment reminder or Mahnung. What matters legally is default: at the latest upon a reminder after the due date — or automatically 30 days after the due date and invoice receipt — the customer falls into default and owes interest. This guide explains the process, what a good reminder contains, and the legal basis.

The typical reminder process

In practice, a multi-stage process has become customary. It is not legally required — a single reminder is enough to establish default — but it is customer-friendly and documents your efforts:

  1. Payment reminder: a friendly note that the invoice is open, usually with a short new deadline. Legally this is often already a first Mahnung.
  2. First/second Mahnung: a firmer request to pay, with a clear deadline and reference to the open invoice (number, date, amount).
  3. Final Mahnung: an explicit demand with a last deadline; announcement of further steps (e.g. dunning proceedings or collection) if unpaid.

What a reminder should contain

  1. Reference to the invoice: invoice number, invoice date, and open amount
  2. The original due / payment date
  3. A clear, new payment deadline
  4. Where applicable, default interest and reminder costs, if default has begun
  5. Your bank details for payment

Default and default interest

When default begins and what interest you may charge depends on the country’s law — pick yours:

Rules for your country:

In Germany, default begins at the latest upon a reminder after the due date (§286 BGB). Without a reminder, the debtor falls into default automatically 30 days after the due date and receipt of the invoice — for consumers only if notified on the invoice. From default you are entitled to interest under §288 BGB: the base rate plus 9 percentage points between businesses, plus 5 points for consumers. For B2B there is also a €40 late-payment lump sum (§288 (5) BGB).

Note: This guide provides general information and is not a substitute for legal advice. Deadlines, interest rates, and conditions can change; the laws currently in force govern.

Frequently asked questions

What is the difference between a reminder and a Mahnung?
Colloquially, a payment reminder (Zahlungserinnerung) is the friendly first note and a Mahnung is the firmer demand. Legally there is no such distinction: even a payment reminder can be a Mahnung within the meaning of §286 BGB and put the debtor in default.
When does a customer fall into default?
At the latest upon a reminder after the due date, the debtor is in default (§286 BGB). Without a reminder, default begins automatically 30 days after the due date and receipt of the invoice — for consumers, however, only if they were expressly notified of this on the invoice. A concrete payment date on the invoice can also trigger default without a reminder.
How many reminders must I send?
No specific number is legally required — the common three-stage process is commercial practice, not law. In principle, one reminder is enough to establish default. After that, you can initiate legal steps (e.g. dunning proceedings).
Can I charge default interest?
Yes, from the point of default. In Germany, under §288 BGB default interest is the base rate plus 9 percentage points for transactions between businesses, and the base rate plus 5 points for consumers. In Austria, higher default interest applies to B2B transactions under §456 UGB. For business transactions, a flat fee for collection costs may also apply.

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