Maximum heat tariffs in 2025: variable tariff slightly lower, fixed costs almost the same

Summary:

• ACM sets the maximum tariffs for households connected to heat networks pay in 2025
• In 2025, households will pay no more than 43.79 euros (VAT included) per gigajoule, while the fixed costs remain virtually the same
• Suppliers must keep their tariffs below the maximum tariff set by ACM

Households that are connected to heat networks will, in 2025, pay no more than 43.79 euros per gigajoule (GJ) for their heat, VAT included. This is almost 3 euros less than last year. The fixed costs for standard users will remain virtually the same (from 759.88 euros to 760.77 euros per year). This has been revealed by the calculation of the maximum heat tariff by the Netherlands Authority for Consumers and Markets (ACM). Heat suppliers must always keep their tariffs below the maximum tariff set by ACM.

Each year, ACM sets the maximum heat tariffs on the basis of the methodology that has been laid down in the law. In addition, ACM sees to it that heat suppliers do not use the maximum tariffs to make unreasonable profits. Each year, ACM publishes a Financial-returns Monitor. The 2023 monitor revealed that the returns varied tremendously among heat suppliers (ranging from -22 percent to +21 percent with an average return of 1.03 percent). To get more insight to the returns of heat suppliers, ACM is currently conducting a study into five heat suppliers. ACM expects to publish the preliminary findings of that study early next year.

How does ACM calculate the heat tariffs?

The method that ACM must use for determining the maximum tariffs has been laid down in the Dutch Heat Act (in Dutch: Warmetewet), the heat decision (in Dutch: warmtebesluit), and the heat regulation (in Dutch: warmteregeling). The maximum heat tariffs are linked to the average costs that a household with a gas-fired boiler has to pay for heating and hot tap water. This is also called the natural-gas reference price or the ‘no-more-than-otherwise principle’ (in Dutch: niet-meer-dan-anders principe).

The maximum tariff per GJ is based on the average natural-gas price of fixed contracts for the supply of gas from 1 January 2025. ACM calculates the maximum fixed costs for heat on the basis of the average maintenance costs and depreciation costs of a gas-fired central-heating boiler as well as the system operation costs, the metering tariffs, and the fixed supply tariffs for natural gas. Heat consumers have to pay for their heat interface units too. The maximum rental price for the heat interface unit is calculated on the basis of the average costs that suppliers incur for this (the costs for the heat interface unit are subsequently deducted from the fixed supply tariffs for natural gas).

Breakdown of fixed supply tariffs in 2025
 

Consequences of heat tariffs ‘emergency act’

The Ministry of Climate Policy and Green Growth (KGG) this year submitted an emergency bill for making heat more affordable. With this emergency legislation, three changes are made to the maximum tariffs: (1) After 2024, real tax increases on natural gas will no longer be included in the variable tariff, (2) from 2025, ACM can use different reference dates when determining the average natural-gas price for fixed contracts, and (3) when the user costs of natural gas are determined, the average of available maintenance contracts for central-heating boilers is taken into account instead of all-in service contracts. In a reversal, the Ministry subsequently laid down in a ministerial regulation that the all-in service contracts need to be taken into account for 50 percent after all. As a result, the effect of the emergency legislation is less considerable than previously expected. The changes under (1) and (2) are only relevant for the tariffs of 2026. See the factsheet with this press release for a further explanation.

Preparing for the ‘new Dutch Heat Act’

In addition to the ‘emergency bill’ aimed at making heat more affordable in the short term, the Ministry of KGG submitted a new Dutch heat act (the bill for the Dutch Collective Heat Act. In Dutch: Wet Collectieve Warmte or WCW) to the Dutch House of Representatives. Under this new act, it is planned to gradually phase out the ‘no-more-than-otherwise principle’. At the moment, it is not yet known when the new legislation will come into effect, but it is not expected to be introduced before 2026. It is also laid down in the law that, for the first two years, ACM will still set the heat tariffs using the ‘no-more-than-otherwise principle’.