Foundation risk and your Dutch mortgage: the NHG rules from 2027

Many older buildings in Amsterdam stand on wooden piles, and when you buy a canal house or a 1900s apartment, nobody has usually looked at what is under it. From 1 January 2027, that foundation can affect how much you are allowed to borrow. NHG, the Dutch National Mortgage Guarantee, will require lenders to factor in the expected repair costs when a home has a high foundation risk. The rule is part of NHG's new terms for 2027, published on 30 October 2026.

What NHG is and why it matters here

NHG is a government-backed guarantee on your mortgage. If you can no longer pay, for example after losing your job or a divorce, NHG can help find a solution and, as a last resort, waive a remaining debt after the home is sold. Lenders usually give a lower interest rate on a mortgage with NHG, and you pay a one-off fee of 0.4 percent of the loan. In 2027 the limit goes up to €500,000.

That limit means the new rules will not touch every Amsterdam purchase. The median sale price in the city was €583,839 in the third quarter of 2026, according to the Amsterdam estate agents' association MVA. If you buy with NHG, they will. NHG has also said it wants lenders to use the same approach for mortgages without the guarantee. Whether and when that happens is not known.

How the new rules work

Since 1 April 2026, every Dutch valuation report has included a foundation risk class, from A (lowest) to E (highest). It comes from a separate foundation risk report based on FunderMaps, a national foundation database, and model calculations. For many buildings, nobody has inspected the foundation itself.

From 2027, for a mortgage with NHG:

• Class A, B or C: no extra requirements.
• Class D or E: an exploratory foundation survey is required. An expert visits the property, measures tilt and cracks, and rates the risk as low, medium or high.
• A low or medium result changes nothing for the mortgage.
• A high result means the lender must include the estimated repair costs. You can still get a mortgage with NHG, but possibly a smaller one.

The rules apply when you buy an existing home, increase your mortgage or refinance with a higher loan. What counts is the date of the lender's binding offer. If it is issued on or after 1 January 2027, the new rules apply, even if the valuation was done earlier. A valuation report stays usable for six months.

How repair costs reduce your borrowing

The report gives the repair cost as a range. The lender takes the midpoint and works out what that amount would cost per month as a 30-year repayment loan at the test rate set by the Dutch financial regulator, the AFM. That monthly amount comes off the maximum housing cost you are allowed under Dutch lending rules. If you have more than €25,000 of your own money set aside for foundation repair, the part above €25,000 can be deducted from the repair estimate. Since 1 October 2026, homes in class D or E already have cost estimates from KCAF, the Dutch knowledge centre on foundation problems, in an annex to the foundation risk report.

Why Amsterdam buyers should pay attention

The city tracks subsidence with more than 11,000 active measuring bolts on buildings in Centrum, West, Zuid, Oost and Noord. The data is public, and the latest readings are from October 2026. In its checklist for foundation surveys, the city notes that buildings from before 1880 rarely have usable archive records, so a survey of the foundation itself is more often needed.

A risk class is an estimate, not a verdict. KCAF describes it as a pointer to a possible next step. A class E building may have a sound, already repaired foundation that was simply never registered. Nationally, reports to the Dutch foundation helpline rose by 280 percent in the summer of 2026 compared with a year earlier. That is a national figure; there is no separate number for Amsterdam.

What to do if you are buying

• Before you bid, ask the seller for any foundation survey, repair report or subsidence data, and check what FunderMaps shows for the building.
• If in doubt, arrange an exploratory survey early. According to KCAF, approved firms start at €295, and the survey is valid for up to three years.
• Plan for the time it takes. If your binding offer falls in January, the new rules apply even if you started in December. Make sure your financing condition in the purchase agreement leaves enough room.
• In an apartment building the foundation is a shared concern, and repairs usually go through the owners' association. Read our guide to checking the owners' association before you bid.

A buying agent can raise these questions before you make an offer. The risk class comes from the valuation report, so it helps to know the foundation risk before the valuation is ordered.

If you are selling

Your buyer will see the risk class in their valuation report. With class D or E and an NHG mortgage, they will need a survey from 2027, often after the purchase agreement has been signed. If you have survey reports or proof of repair, share them with the sale documents and have them recorded in FunderMaps and the national foundation repair register. KCAF points out that known defects and survey results may be part of the information a Dutch seller has to disclose. Discuss your own situation with your agent or a lawyer.

Sources (in Dutch): NHG, press release of 27 October 2026, foundation risk assessment framework, transition rules and guidance for buyers; KCAF, foundation surveys, FunderMaps and reports to the foundation helpline; City of Amsterdam, measuring bolt dataset and foundation survey checklist; Makelaarsvereniging Amsterdam, Q3 2026 figures.