Fixed, variable or dynamic: which energy contract suits you?

In short
The contract type sets only the energy cost. Grid costs, levies and VAT are the same for all contracts. Fixed: the price per kWh stays fixed for the whole term. Variable: the price follows an index every month or every quarter. Dynamic: the price follows the wholesale price by the hour or quarter of an hour. You need a digital meter for this. For a typical household, dynamic was the cheapest on average in 2025 and fixed the most expensive. For your household, it depends on when you use electricity. You may end a fixed contract without a penalty. The supplier may still charge you the fixed fee. Enter your own consumption in the V-test (the independent price comparison) of the Flemish regulator (Vlaamse Nutsregulator).

Often heard: what is true?

What is on your bill?

According to the CREG, the federal energy regulator, your bill has four parts:

1. Energy cost. The price per kWh plus a fixed fee per year. According to the CREG, this is the only part your supplier sets itself.
2. Grid costs. Transmission (Elia, the transmission grid operator) and distribution (Fluvius, the distribution grid operator). The regulator approves the tariffs. You do not choose your grid operator.
3. Levies. Statutory contributions to the government.
4. VAT. Since 1 April 2023, the VAT rate on electricity and natural gas has been permanently 6 per cent, according to the FPS Finance (the federal finance ministry).

The contract type affects only the first part. You will find more explanation in "How is the electricity price set? From gas plant to your bill".

One grid cost depends on your behaviour: the capacity tariff (capaciteitstarief). Fluvius measures your highest quarter of an hour of the month, in kW. Everyone with a digital meter pays for at least 2.5 kW. According to the Vlaamse Nutsregulator, the Flemish average in 2026 is about €53.39 per kW per year, excluding VAT. The tariff differs per grid operator. A low energy price does not change this.

How the three types work

Fixed

The price per kWh stays the same until the end of the term. For fixed-term contracts, the supplier may not change the price unilaterally, writes the FPS Economy (the federal economy ministry, 2022).

What you need to know:

• Term. The tariff sheet shows how long the price stays fixed.
• The end. What happens after the term is in the conditions. On 2 July 2026 the Chamber of Representatives passed a law. Because of it, suppliers must warn you at least two months ahead when a contract renews automatically. The law applies, broadly, to contracts from 1 January 2027. There is no confirmation that it has already been published in the Belgian Staatsblad (Official Gazette).
• Ending early. The electricity and gas laws ban any fee when a household ends its contract, says the Ombudsdienst voor Energie (the energy ombudsman). The Vlaamse Nutsregulator does report that suppliers can charge the fixed fee for half a year or a full year. The Ombudsdienst calls a fixed fee for a full year a (disguised) termination fee. Under the same law of 2 July 2026, the supplier may charge the fixed fee only pro rata, for contracts from 1 January 2027.
• Switching. Allow about 3 weeks for a switch, according to the Vlaamse Nutsregulator.

Variable

The price follows an index of the wholesale market. This index can change every month or every quarter. Test-Aankoop (the Belgian consumer organisation) lists dozens of different indexes. Some follow the price for the next month or the next year (forward). Others follow the price for the next day (spot). According to Test-Aankoop (2022), spot is usually cheaper, but its price swings more.

What you need to know:

• What you read is not always what you pay. With a spot contract, the tariff sheet shows the last known value. You learn this month's price only afterwards.
• The supplier may change the price. For open-ended contracts this is allowed, if you can cancel without a termination fee (FPS Economy). The price formula usually stays fixed for at least a year, according to the Vlaamse Nutsregulator.
• Fixed fee. When you leave, the supplier may charge at most six months of fixed fee for a variable contract (VRT, the Flemish public broadcaster, 2023).

Dynamic

The energy price changes per hour or per quarter of an hour. It follows the Belgian wholesale price for the next day (day-ahead). You know these prices a day ahead. Since 1 October 2025 they exist per quarter of an hour, writes Test-Aankoop. Some contracts still bill per hour.

What you need to know:

• Digital meter. You need a digital meter. You also give your grid operator permission to pass the quarter-hour values to your supplier. According to Test-Aankoop, a meter with an exclusive night tariff (for example for storage heating) is excluded by most suppliers.
• Electricity only. According to the Vlaamse Nutsregulator, dynamic prices exist only for electricity.
• Fixed fee. On average €70 per year in May 2026, up to €130 at some suppliers (Test-Aankoop).
• Price peaks. The highest hourly price in 2025 was €517.57 per MWh. That is more than 51 cents per kWh, for the energy part only. The lowest was minus €462.33 per MWh. Both figures appear, excluding VAT, in the Prijzenrapport 2025 (Price Report 2025) of the Vlaamse Nutsregulator.
• Negative prices. The energy part then costs nothing or is even negative. Grid costs, levies and VAT remain.
• Availability. Customers with a digital meter may ask for a dynamic contract from any supplier with more than 200,000 customers. This is in European Directive 2019/944, article 11.

An example from Test-Aankoop for Friday 22 May 2026, energy part only, including VAT: from 1 pm to 2 pm about 0.74 cents per kWh, and from 8 pm to 9 pm 18.58 cents. If you charge 30 kWh between 8 pm and 9 pm, that costs 30 × €0.1858 = about €5.57. Between 1 pm and 2 pm it is 30 × €0.0074 = about €0.22.

What did they cost on average?

The Vlaamse Nutsregulator calculates the cost for a typical household without a social tariff every year. In 2024 that household paid about €1,040 for electricity on a dynamic contract. That was €45 less than variable and €299 less than fixed (VRT). The household used 3,500 kWh a year.

In 2025 dynamic was the cheapest again, at about €1,203 on average. Variable cost €62 more and fixed €193 more (Prijzenrapport 2025 of the Vlaamse Nutsregulator, 7 May 2026). In 2024 fixed cost €254 more than variable on average. In 2025 it was €131 more for electricity and €179 more for gas. Fixed and variable moved closer together.

Two caveats:

• These are averages over two years. A fixed contract does protect you against a price rise during its term. You did not see that benefit in those two years.
• The figures apply to average consumption. If you shift consumption to cheap hours, you can save more. If you use a lot in expensive hours, you can pay more (Vlaamse Nutsregulator).

In December 2025, 0.8 per cent of Flemish households had a dynamic contract. Of the households without a dynamic contract, about 26 per cent had a fixed contract (Vlaamse Nutsregulator).

Which type suits whom?

A household without flexibility or a digital meter. You use mostly in the evening and can shift little, or you have a classic meter. Then dynamic is not possible or brings little. Choose between fixed and variable. Fixed gives peace of mind and a set expense. Variable was cheaper on average, but the price can rise.

Electric car, heat pump or home battery. You can control these large users. A car that charges in the cheapest hours brings the most, writes Test-Aankoop. In 2025, evening charging cost about €152 more than charging in the afternoon, according to CREG figures that Test-Aankoop cites. Watch your monthly peak. If all appliances start together in the cheapest quarter of an hour, your capacity tariff rises. Each extra kW of monthly peak costs you €53.39 per year on average, excluding VAT. A charger or battery with smart control helps.

Solar panels. A separate price for your injection appears on the tariff sheet.

• With a fixed or variable contract, the injection price is also fixed or variable, according to vlaanderen.be. You sign the injection contract (terugleveringscontract) with your current supplier or another one.
• A variable injection price can turn negative in some months. In 2025 an estimated almost 29,000 households with solar panels (prosumers) received a negative payment for at least one month (Vlaamse Nutsregulator, on variable contracts). That is about 3 per cent of the prosumers with a digital meter (own calculation).
• With a dynamic contract, the injection price follows the hourly price and can turn negative. You then pay to inject power. It is then best to use more power yourself.

You can read more about your meter and injection in "Solar panels in 2026: without a backwards-running meter".

Comparing quotes fairly

1. Start with the V-test. This is the independent price comparison of the Vlaamse Nutsregulator. You enter your current contract and your consumption. It shows offers for new customers, not your exact next bill. For dynamic contracts, you upload quarter-hour values from Mijn Fluvius (your online customer account with Fluvius).
2. Read the tariff sheet. Look at the energy price per kWh and the fixed fee per year. A low kWh price with a high fixed fee can still cost more.
3. For variable: which index and how often? Ask whether it is spot or forward, and whether the price changes monthly or quarterly.
4. Term and end. How long does the price stay fixed? What happens afterwards?
5. Cancellation conditions. What does the supplier charge if you stop early? The V-test warns about unfavourable conditions, writes the VRT.

Check your current contract too. According to the VRT (October 2026, based on CREG figures), about 700,000 households overpay an average of €700 a year for electricity and gas. With the CREG Scan and the V-check, via the QR code on your bill, you see in two minutes where you stand.

What now?

1. Find your last annual statement. Note your consumption in kWh, your fixed fee and your contract type.
2. Open Mijn Fluvius. Check whether you have a digital meter and how high your monthly peaks are.
3. Fill in the V-test with your own consumption. If you have a digital meter, upload your quarter-hour values.
4. Can you easily shift your consumption, for example charge a car or let a boiler heat up? If so, compare one dynamic contract with fixed or variable. If not, choose between fixed and variable.
5. Check the fixed fee and the cancellation conditions before you sign.

Sources and disclaimer

This text is based on:

• CREG: how the energy price is made up
• FPS Finance: VAT on energy
• Vlaamse Nutsregulator: capacity tariff (capaciteitstarief)
• Vlaamse Nutsregulator: steps to switch your energy contract
• Vlaanderen.be: V-test
• Ombudsdienst voor Energie: fixed fees versus termination fees
• FPS Economy: your rights if you have a problem with your energy contract (2022)
• Directive (EU) 2019/944, article 11
• Vlaamse Nutsregulator: Prijzenrapport 2025 (RAPP-2026-07, 7 May 2026)
• VRT: VREG price report on 2024 (2025)
• VRT: how not to get caught out when you switch (2023)
• Chamber of Representatives, bill 56 1537: text adopted on 2 July 2026 and committee text
• VRT: check your energy contract (October 2026)
• Consumer organisation Test-Aankoop: dynamic tariffs, dynamic contracts 2026, energy purchasing power law, press release of 2 July 2026, variable tariff, indexation parameters

Test-Aankoop is a consumer organisation and not an official source. The figures for 2025 come from the report of the Vlaamse Nutsregulator itself. This is general information, not personal advice. Tariffs and rules can change. Position as of 30 October 2026.