Around the canals and student housing near TU Delft, numerous free-sector contracts are under pressure. A recent ruling by the Hoge Raad has sharply restricted landlords’ scope to automatically increase rents via the WOZ value, affecting thousands of households in the region.
Background to the case
In recent years, landlords have applied WOZ increases directly to the rent price. A 15 percent rise in the WOZ value sometimes led to an equivalent percentage rent increase, regardless of inflation or maintenance. Tenants in neighbourhoods with many expats and students began initiating proceedings over this.
The Hoge Raad’s ruling
The Hoge Raad has set out three clear lines:
1. WOZ linkage is not automatic justification
A WOZ increase often reflects speculative market value rather than an actual improvement to the leased property. A tenant is not required to pay the speculative premium borne by the owner.
2. Tenant may require substantiation per property
Landlords must demonstrate that the WOZ increase is linked to an actual rise in quality, maintenance expenditure or objective market dynamics in the neighbourhood — not merely a paper valuation by the municipality.
3. Unreasonably burdensome clauses are voidable
WOZ linkages without a cap or exception clause are classified by the Hoge Raad as unreasonably burdensome (article 6:233 BW). This renders them voidable — the tenant may claim that the clause be declared inapplicable.
Consequences for tenants in the region
- Tenants with a WOZ clause can challenge increases exceeding inflation plus maintenance
- Already paid “excessive” increases can be reclaimed for up to three years
- Tenants must lodge a written objection within six weeks of the announcement
- In case of dispute: apply to the Huurcommissie (regulated sector) or the kantonrechter (free sector) at the Rechtbank Den Haag
What must landlords adjust?
Existing lease agreements:
- Revise the WOZ linkage to an inflation-plus-maintenance formula
- Have written substantiation ready for future increases
- Do not automatically threaten termination upon a tenant’s objection — this too has become riskier following the ruling
Broader implications
The ruling fits a trend in which courts increasingly provide tenant protection in the free sector. Limitations on other automatic increase mechanisms (CPI linkages without a cap, energy-price pass-through) are also expected in 2026 — politicians have flagged this as a legislative topic for 2027.
Practical advice for tenants
Have you received a WOZ-based increase in the past three years that you considered disproportionate? Request written substantiation from the landlord, retain all correspondence, and consult the Juridisch Loket Delft or a tenancy-law lawyer if necessary. You may also contact the Arslan office at Phoenixstraat 16, 2611 AL Delft (telephone 070 - 4500 300). The three-year reclamation period (article 3:309 BW) runs from the moment you could reasonably have been aware of the unlawfulness.