When a customer doesn't pay on time, you want to take action. But which letter do you send exactly? In practice, the terms reminder and WIK letter are often used interchangeably, while they are two fundamentally different documents. In this article we explain the difference clearly, so that you always send the right letter at the right time.
What is a reminder?
A reminder, also called a payment reminder, is a letter in which you ask your customer — politely or urgently — to pay an outstanding invoice. A reminder is form-free: there are no legal requirements for its content or format. You can send a reminder as often as you like.
Most entrepreneurs first send a friendly reminder, followed by a stricter second one. This is good practice for preserving the relationship with your customer, but it is not legally required. A reminder, however, does not give you the right to charge collection costs.
What is a WIK letter?
A WIK letter is a legally required demand letter under the Dutch Debt Collection Costs Act (Wet Incassokosten, or WIK). When you want to charge collection costs to a consumer, you are legally required to first send a WIK-compliant 14-day letter. Without this letter, you cannot legally claim collection costs.
The WIK letter must meet a number of legal requirements. You must give the debtor a payment term of at least 14 days, counted from the day after receipt of the letter. Additionally, you must state the exact amount of collection costs that will be owed if payment is not made on time. You can also send a WIK letter by email. Read more about the content requirements on our page What is a WIK letter?.
The key differences
Below you will find an overview of the key differences between a regular reminder and a WIK letter:
| Reminder | WIK letter | |
|---|---|---|
| Legally required | No | Yes (for consumers) |
| Payment term | Freely determined | Minimum 14 days after receipt |
| State collection costs | Not required | Required (exact amount) |
| Right to collection costs | No | Yes, after term expires |
| Form requirements | None | Specific legal requirements |
| Target group | Everyone | Required for consumers |
When do you send which letter?
The answer depends on your situation and your goal:
- Friendly reminder: send a regular reminder when you want to preserve the customer relationship and expect that a reminder will be sufficient.
- Claiming collection costs (consumer): always send a WIK letter first. Without this letter, you cannot legally charge collection costs.
- Business client: for a business debtor, a WIK letter is not legally required, but sending one is recommended as a professional and transparent approach.
In practice, many entrepreneurs choose to first send one or two reminders and then, if payment is not received, send a WIK letter as a final step before engaging a collection agency.
What if you don't send a WIK letter?
If you do not send a WIK letter before charging collection costs to a consumer, those collection costs are not owed. A judge will reject the collection costs in that case. You therefore lose not only the costs themselves, but also the legal process costs incurred.
Additionally, you run the risk that a judge will scrutinize your entire claim more critically. Not following the statutory procedure can weaken your position, even if the principal claim itself is justified. You also miss out on the statutory interest you could have claimed.
Want to calculate the correct collection costs right away? Use our free collection costs calculator to determine the exact amount.
Conclusion
A reminder and a WIK letter serve different purposes. The reminder is a non-binding notification, while the WIK letter is a legal requirement for charging collection costs to consumers. Make sure you always send the right letter at the right time. Via wikbriefversturen.nl you generate a legally correct WIK letter within 2 minutes, complete with the correct calculation and payment term.