C90 principle in dentistry: what you need to know about no-show costs in 2025

automatische afspraakherinneringen tandartspraktijk no-show vermindering TurnUp

The C90 principle is a key regulation in Dutch dentistry designed to help practices recover lost income caused by patient no-shows. With an average of 3.6 missed appointments per provider per week, no-shows result in significant financial losses for dental practices. Did you know that as of April 2025, C90 rates have increased to €20 per 5 minutes of reserved treatment time?

What Exactly Is the C90 Principle?

The C90 principle is a nationwide guideline that grants dentists and dental hygienists the right to charge patients who fail to attend their appointments. The declaration code C90 stands for “Missed Appointment” and allows practices to recover costs for the time and resources reserved.

According to the Dutch Healthcare Authority (NZa), dentists may charge a C90 fee for missed appointments or cancellations made within 24 hours. This compensates for the lost time that could not be allocated to other patients.

Key Features of the C90 Regulation

  • Applies to appointments not attended or cancelled too late (within 24–48 hours)
  • May cover up to the full cost of the planned treatment
  • Not reimbursed by basic or supplementary health insurance
  • Patients must be informed of the policy in advance

C90 Rates in 2025

From April 1, 2025, many practices have adopted the new rate of €20 per 5 minutes of reserved time.
Here’s what that means for patients:

  • 10-minute appointment = €40
  • 20-minute appointment = €80
  • 30-minute appointment = €120

Longer treatments can easily add up to several hundred euros.
Some practices still apply the previous rate of €17.50 per 10 minutes, but the general trend is toward higher rates due to increasing operational costs and growing scheduling pressure.

The Financial Impact on Your Practice

With an average of 3.6 missed appointments per provider per week, no-shows can cause significant financial losses. For a typical dental practice, this translates into:

  • 3.6 missed appointments × an average of 20 minutes = 72 minutes of lost time
  • At €80 per 20-minute slot, this equals €288 in lost revenue per week.
  • Annually: €288 × 50 working weeks = €14,400 per provider.

For a two-provider practice, that’s nearly €29,000 per year — not including indirect costs like staff time and overhead.

Legal Requirements and Patient Communication

The KNMT (Royal Dutch Dental Association) advises members not to charge patients who cancel at least two working days in advance. For a C90 declaration to be legally valid, several conditions must be met:

Mandatory conditions:

  • Patient information: The patient must be clearly informed of the policy in advance.
  • Written communication: The policy must be visible on the website, in brochures, or on appointment cards.
  • Reasonableness: The charge must not exceed the cost of the intended treatment.
  • Actual time loss: The reserved time must truly have been lost.

These costs are not covered by basic or supplementary health insurance and must be paid by the patient directly.

How Patients Can Avoid C90 Fees

For patients, preventing a C90 charge is simple:

  • Cancel appointments at least 24–48 hours in advance (depending on practice policy)
  • Add reminders to personal calendars and set alerts
  • Contact the practice promptly in case of illness or uncertainty
  • Use digital reminders via email or SMS

For practices:

  • Communicate your no-show policy clearly
  • Send automated reminders
  • Evaluate each situation individually before applying a C90 charge

The Role of Modern Technology

While the C90 principle helps recover lost revenue, prevention is better than cure.
Modern AI technology can help practices predict and prevent no-shows — avoiding the need to issue C90 fees altogether.

TurnUp’s AI-driven solution offers:

  • 85% accuracy in predicting no-shows
  • Automatic slot refilling when cancellations occur
  • Smart waiting list management combining internal and external lists
  • Targeted communication with high-risk patients

By preventing no-shows instead of compensating for them, you avoid revenue loss and maintain patient satisfaction. A win-win for both the practice and the patient.

Practical Steps for Implementation

For dental practices looking to optimize their no-show management:

  1. Improve communication: Clearly state your C90 policy on your website and appointment confirmations.
  2. Set up reminders: Send automated reminders 48 and 24 hours before appointments.
  3. Analyze data: Track frequent no-show patients and identify trends.
  4. Adopt preventive measures: Implement AI tools for prediction and slot optimization.
  5. Show flexibility: Be understanding of genuine emergencies while maintaining consistency.

From Reactive to Proactive

The C90 principle remains an essential safeguard for dental practices facing financial losses from no-shows.
With the rate increase in 2025, applying it correctly becomes even more important.
At the same time, modern technology offers powerful tools to address the problem proactively.

Instead of only charging fees after missed appointments, AI-powered prediction and automation help you fill your schedule efficiently and maintain patient satisfaction.
After all, a fully booked, no-stress schedule is far more valuable than recovering costs from missed appointments.

Want to learn how AI can help your practice reduce no-shows instead of compensating for them?
Book a free demo and discover how to increase your scheduling efficiency without burdening your patients with C90 fees.

Disclaimer: This article is intended for informational purposes only. Always consult official NZa guidelines and your legal advisor for your specific situation.

What does the C90 principle mean for dental practices?

The C90 principle is a regulation in Dutch dentistry that allows dentists to charge fees for missed appointments, also known as no-shows. This principle, defined under billing code C90, is designed to compensate dental practices for the lost time and revenue caused by patients who fail to attend or cancel too late. As of April 2025, the C90 rate has increased to €20 per 5 minutes of reserved treatment time, helping dentists better manage the financial impact of no-shows.

When can a dentist charge C90 fees?

Dentists are allowed to charge C90 fees when patients fail to attend their appointment or cancel too late (within 24–48 hours). This means that if a patient does not cancel in time, the dentist can bill for the lost time. The purpose of this rule is to protect dental practices from the financial impact of missed appointments. It is important, however, that patients are informed about this policy in advance to avoid any surprises.

Are C90 fees covered by health insurance?

C90 fees, also known as charges for missed appointments, are not covered by basic or supplementary health insurance. This means that if a patient misses an appointment and the dentist applies C90 fees, the patient must pay these costs out of pocket. It’s therefore important for patients to cancel or attend their appointments on time to avoid unnecessary expenses.

How much can a dentist charge for a no-show?

In the case of a no-show, a dentist may charge costs according to the C90 rate, which, as of April 2025, is set at €20 per 5 minutes of reserved treatment time. This means that if a patient misses a one-hour appointment, the dentist can charge up to €240, depending on the time reserved. This system is designed to compensate dentists for the loss of time and income caused by missed appointments.

What should patients know about the C90 principle?

As a patient, it’s important to understand the C90 principle, especially with the upcoming rate increase in 2025. Make sure to cancel your appointment in time if you’re unable to attend — preferably more than 24 hours in advance — to avoid extra costs. Be aware that C90 fees are not covered by health insurance, and dentists are required to inform patients about this policy in advance. This helps prevent misunderstandings and unexpected charges.