You have bought a home in the Netherlands. A few months later, the municipality sends a letter with a property value you do not recognise. It may be lower than you paid, higher than you expected, or different from the figure your mortgage adviser used. Beside it sit several tax charges.
This is your WOZ value. It is an official valuation used for Dutch taxes and some other purposes. Understanding it starts with a simple point: the letter is valuing your home for a particular date. It is not telling you what someone will pay for it today.
Three prices can describe the same home
The purchase price records what you and a seller agreed. A mortgage valuation gives a lender information for its lending decision. The WOZ value is the municipality’s annual estimate under Dutch property valuation rules. These figures can differ without any of them being an obvious mistake.
WOZ is short for Wet waardering onroerende zaken, the law governing these valuations. The estimate is based on the property’s features and sales of comparable properties. It also uses legal assumptions, such as valuing the property as available for immediate use rather than reducing its value because a tenant currently occupies it.
Do not treat a gap between your purchase price and the WOZ value as an instant profit or loss. Before deciding that the municipality is wrong, compare the dates and the property details behind both figures.
The date is earlier than you might expect
A WOZ notice for 2026 normally uses property prices as at 1 January 2025. This earlier date is called the waardepeildatum, or valuation date. If you bought in summer 2026, your purchase took place about a year and a half later.
That gap matters in a changing housing market. Imagine a home valued at € 380,000 for the earlier date that later sells for € 415,000. The difference alone does not prove that the original estimate was too low. Market conditions and the property’s condition may have changed.
There is a second date to understand if the home was newly built or altered. The municipality may use the property’s condition at the start of the tax year while keeping the earlier price level. This condition date is the toestandspeildatum. An extension completed during 2025 can therefore affect the 2026 valuation without changing its January 2025 price reference.
You do not need to memorise the Dutch terms. You do need to know whether a figure describes the home before or after building work, and which year’s market is being used.
What actually changes your tax bill?
For an owner who lives in the property, the WOZ value helps determine municipal property tax, a property-related water board charge and the owner-occupied home addition in the income tax return. These are separate calculations.
The municipal property tax is called OZB. Its rate varies by municipality and year. To illustrate the calculation, suppose a municipality charged 0.08%. A WOZ value of € 450,000 would produce an annual OZB charge of € 360. A € 20,000 increase in value would add € 16 at that unchanged rate. These are invented figures for the example, not a current rate quotation.
The income tax addition is called eigenwoningforfait. It adds an amount based on your home’s WOZ value to your taxable income. The addition itself is not the tax you pay. Your income, deductible mortgage interest and other applicable rules influence the final result.
Your municipal bill may also contain charges that do not move directly with the WOZ value. A € 50 rise in the whole bill cannot automatically be blamed on a higher property valuation. Read the individual lines before trying to work out what changed.
If you recently bought, the separate question of which Dutch home-buying costs are tax deductible is worth checking too. Purchase costs and the annual home valuation belong to different parts of your tax paperwork.
Match the notice to the tax year
Filing a return in 2026 does not always mean using the 2026 WOZ notice. If the return is for income earned in 2025, the owner-occupied home calculation uses the WOZ value for 2025. That valuation refers to prices on 1 January 2024.
There are therefore three dates in play: the filing year, the tax year and the valuation date. A simple folder named after each tax year can prevent a lot of confusion. Save the original notice and any later corrected notice together.
Check any value already filled in on the return. If you moved during the year, the period for which the home was your main residence can matter as well. Getting the amount right is only one part of reporting a home correctly.
Read the report behind the number
The taxatieverslag is the municipal appraisal report. You can normally access your report through the municipality or MijnOverheid using DigiD, or request it from the municipality. It explains the property details and comparisons used in the valuation.
Start with facts you can check: usable floor area, plot size, property type, construction year and outbuildings. Then consider condition and location. A small apartment facing a busy road should not be treated as identical to a larger, fully renovated apartment overlooking a courtyard without allowing for those differences.
The report commonly includes a few comparable sales. They are examples supporting the estimate, not necessarily every sale considered in the valuation process. A comparison does not have to be identical to be useful. What matters is how the differences were handled.
You can look up other homes’ WOZ values in the public WOZ register. Those values are not their sale prices. If a neighbour’s figure is lower, that gives you a reason to investigate. It does not, by itself, establish the right value for your home.
If the valuation looks wrong
Contact the municipality with a clear question. An incorrect floor area is easier to discuss than a general feeling that the amount is unfair. If poor maintenance affects value, explain the condition and provide relevant evidence, such as photographs or existing reports.
The usual objection deadline is six weeks from the date on the notice. Check the instructions on your own letter. Do not assume that asking a question by phone stops the clock. If the municipality treats the conversation as a formal objection, obtain confirmation; otherwise submit an objection within the deadline.
Keep your argument focused on the appropriate valuation date and the relevant property facts. A recent asking price or a large percentage increase is not automatically proof of an error. An objection is a request to correct the valuation, not a guaranteed way to reduce tax.
A higher figure does not give you more spending money
It can feel reassuring to see your home’s value rise. But the figure does not pay for repairs, cover a lost job or refill your savings after moving costs. You can own a valuable property and still have very little cash available.
This matters when deciding whether to make extra mortgage payments. Money used to reduce the loan is generally harder to access than money in a savings account. My discussion of paying off a mortgage or investing explains why flexibility belongs in that decision alongside possible returns.
Some Dutch lenders may accept a higher WOZ value as evidence when reviewing a mortgage interest surcharge. Others require different evidence or apply different conditions. Check your lender’s terms before assuming the notice will reduce your interest rate.
The useful aim is an accurate value, with a clear understanding of what follows from it. Read the report, keep the right year’s notice and investigate specific errors promptly. You can then put the letter away knowing what it means, without mistaking one property estimate for a verdict on your financial wellbeing.