Replacing a gas or oil boiler in Belgium: price, 21% VAT, bans and regional grants
Short answer: A Belgian price guide (Trustup, updated July 2026) puts a replacement boiler at 2,500 to 8,000 euros, fitted and including VAT. Since 29 July 2025, the boiler itself carries 21% VAT, even in a renovation. In Brussels, installing an oil boiler has been banned since 1 June 2025, barring derogations, and the Renolution grants are suspended.
Published on 26 October 2026 · Updated on 26 October 2026
VAT: 21% on the boiler, 6% only on certain parts
Since 29 July 2025 the Federal Public Service Finance charges VAT at the standard 21% rate on installing or replacing a central-heating boiler that runs on natural gas or oil, including in homes over 10 years old that used to qualify for 6%. The reduced rate remains for the "non-specific" part of the installation, provided the other renovation conditions are met.
| Item | Rate |
|---|---|
| Gas or oil boiler, flue, fuel supply, tank, boiler controls, built-in circulation pump | 21% |
| Radiators, underfloor heating, hydraulic pipework, expansion vessels, thermostat, stand-alone circulation pump | 6% if all conditions are met |
| Servicing and repair of an existing fossil-fuel system | Not affected by the increase |
| Fully non-fossil heating (a heat pump, for example) | Reduced rate possible if the legal conditions are met |
| Hybrid system (fossil boiler + heat pump) | Same rules as a fossil-fuel installation; for a single global price the tax authority accepts a flat-rate split: 35% for the boiler (21%) and 65% for the heat pump and the non-specific part (6% if the conditions are met) |
Two things to check on a quote: the invoice must split clearly what is charged at 21% and at 6%, otherwise the whole invoice is taxed at 21%. Labour hours follow the rate of the part they relate to. The transitional rule for contracts signed by 28 July 2025 only covered VAT falling due by 30 June 2026, so it has expired.
Source: FPS Finance, changed VAT rates for fossil-fuel heating installations.
How much does a boiler replacement cost?
Published Belgian price brackets run from 1,800 to 6,000 euros for a fitted gas boiler and up to 9,000 euros for oil, installation included (Trustup states 'VAT and fitting included' for the overall 2,500 to 8,000 euro bracket). They are market benchmarks taken from Trustup, not FUSE SERVICES prices.
| Type | Bracket given |
|---|---|
| All boilers combined (gas, oil, condensing), VAT and fitting included | 2,500 to 8,000 euros |
| Standard gas boiler (heating only) | 1,800 to 3,500 euros |
| Low-temperature gas boiler | 2,200 to 4,500 euros |
| Condensing gas boiler | 3,000 to 6,000 euros |
| Oil boiler (flat-rate range announced) | 2,500 to 9,000 euros |
What moves a quote: the output you need, the brand, the location (wall-hung or floor-standing), replacing or adapting the chimney or flue, hot-water production, removing the old appliance and any tank, and the condition of the pipework. The same guide mentions 4 hours to 2 days of work depending on the job. Compare at least two or three itemised quotes, with VAT split as described above.
Sources: Trustup, boiler installation cost (updated 6 July 2026) and Trustup, oil boiler cost. Figures differ from one site to another; we use the brackets of a single source for consistency.
Repair or replace: when is it time to change the boiler?
Replace rather than repair when the appliance is old, breaks down often, uses more and more fuel or poses a safety risk (carbon monoxide, leaks, corrosion). We found no official source setting a maximum age: a technician's diagnosis decides.
- Repeated breakdowns, or parts that are hard to find for your model.
- A heating bill that climbs without any change in your habits.
- A service or PEB check report that flags poor efficiency or a safety defect.
- An oil boiler in Brussels or Flanders: the ban on installing oil boilers may stop you from replacing like for like, see below.
If you rent, who pays is a separate question: see boiler breakdown in a rental: who pays?. For the compulsory periodic check, see boiler servicing in Brussels.
Oil boilers banned? The rules region by region
In Brussels you can no longer install an oil boiler since 1 June 2025, even as a replacement, unless a derogation applies. Flanders bans it wherever a gas network is available at the building; Wallonia will do so for existing buildings from 1 January 2031.
| Region | Rule (official source) |
|---|---|
| Brussels-Capital Region | Installation banned since 1 June 2025 (installation date), barring derogation. Natural-gas boilers have been banned since 1 January 2025 in projects made up only of new or new-equivalent PEB units, if the planning permit is filed after that date. |
| Flanders | Since 1 January 2022: banned in new builds and major energy renovations; in an existing building, banned if a gas main is available in front of the building or across the street. Administrative fine of 3,000 euros plus 2,000 euros per unit for breaches. |
| Wallonia | Banned in new buildings since 1 January 2026. For existing buildings: ban on installing or replacing an oil or coal boiler from 1 January 2031; replacing only the burner stays allowed until 31 December 2034; derogations possible. |
An existing boiler can stay in service in all three regions; it is installation and replacement that are regulated. Flanders stresses that the installer must warn you about the ban, but responsibility for the installation lies with the customer.
Sources: Brussels Environment (Bruxelles Environnement), Vlaanderen.be, Wallonie.be.
Grants: Brussels, Flanders, Wallonia in October 2026
The official sources consulted mention no regional grant dedicated to a replacement gas or oil boiler; the remaining support mainly targets heat pumps or whole-home renovation. Always check the current position before signing, because these schemes change fast.
| Region | Status |
|---|---|
| Brussels | The RENOLUTION grants are "currently suspended" according to Brussels Environment (page dated 14 September 2026). Do not budget for any amount. |
| Flanders | Mijn VerbouwPremie was reformed on 1 March 2026. Owner-occupiers in income categories 1 and 2 and other investors can now only get a grant for a heat pump or heat-pump water heater (applications until 31 December 2027); nothing changes for categories 3 and 4, but the pages consulted do not detail which heating works qualify for them: check before counting on a grant. Sample amounts for categories 1 and 2: 1,500 euros for an air-to-water heat pump, 800 euros for a hybrid, 4,000 euros for a geothermal one (grant capped at 20% of the invoice in category 1, 25% excluding VAT in category 2). |
| Wallonia | The heating grants ended on 14 February 2025. Since 1 October 2026 support takes the form of loans (Rénopack at 0% with a 15 to 50% reduction of the amount to repay depending on income, and Rénoprêt), reserved for homes with a PEB label of G, F or E whose works reach at least D or C. |
In practice no grant is open in Brussels and Wallonia has moved to loans; in Flanders, check your income category and eligible works on the official Mijn VerbouwPremie website. Energy-supplier offers or municipal grants may exist: ask your commune.
Sources: Brussels Environment, RENOLUTION grants, Vlaanderen.be, Mijn VerbouwPremie changes 2026, Wallonie.be, new support scheme, Wallonie.be, end of heating grants in February 2025.
Gas, oil or heat pump: comparison table
In 2026 the gas boiler is the only fossil-fuel boiler that can still be fitted in an existing Brussels home, but at 21% VAT; only a fully non-fossil system such as a heat pump can still claim the reduced rate. The table sums up the points verified in this article.
| Criterion | Gas | Oil | Heat pump |
|---|---|---|---|
| VAT on the appliance, renovation | 21% | 21% | Reduced rate possible if the legal conditions are met |
| Installation in Brussels | Possible in existing buildings; banned in fully new projects (permit after 1 January 2025) | Banned since 1 June 2025, barring derogation | No ban of that kind mentioned |
| Installation in Flanders | No ban mentioned in the sources consulted | Banned if gas is available in the street | Mijn VerbouwPremie grant (lower amounts since March 2026) |
| Installation in Wallonia | Listed by Wallonia as an alternative where gas is available | Banned from 2031 in existing buildings | Rénopack or Rénoprêt loans depending on PEB label |
| Fitted price | See the brackets above | See the brackets above | Not priced here: request a quote after a survey of the home |
The choice depends on the home (insulation, heat emitters, available space) and on whether you have gas access. Have a professional run the comparison, based on a quote.
PEB rules and steps to follow before you sign
In Brussels, an installed boiler stays subject to the periodic PEB check by an approved technician (every 2 years for gas, every year for oil), and a check is also required after certain work on the burner. Brussels Environment also asks owners of an atmospheric boiler connected to a shared chimney to carry out a feasibility analysis for replacing it. Frequencies and approvals are detailed in our article on boiler servicing in Brussels.
- Check what is still allowed in your region: oil banned in Brussels, restricted in Flanders, postponed to 2031 in Wallonia.
- Ask for two or three itemised quotes, with VAT split between the boiler (21%) and the parts that may qualify for 6%.
- Check the installer's approval (for example PEB technician GI or GII for gas and L for oil in Brussels) and ask for it in writing.
- Confirm the status of any grant or loan before signing: in Brussels nothing is open at the moment.
- Keep the itemised invoice and the commissioning report; they are useful for the next periodic check.
For a breakdown call-out or an on-site opinion in Brussels, see the heating engineer page. This comparison is not a quote.
Sources: Brussels Environment, periodic PEB check and Brussels Environment, new heating rules 2025.
Your questions before we arrive
What people in Brussels, Walloon and Flemish Brabant ask before confirming.
Can you still get 6% VAT on a gas boiler?
Can I replace my oil boiler with a new one in Brussels?
Is there a Renolution grant for a boiler in 2026?
How long does a boiler replacement take?
- SPF Finances (fin.belgium.be) : modification des taux de TVA pour les installations de chauffage fossiles
- Bruxelles Environnement : Les primes RENOLUTION (suspendues)
- Bruxelles Environnement : nouvelle réglementation chauffage dès 2025
- Bruxelles Environnement : contrôle périodique PEB des chaudières
- Vlaanderen.be : stookolieketelverbod
- Vlaanderen.be : wijzigingen Mijn VerbouwPremie vanaf 2026
- Wallonie.be : chaudières au mazout et au charbon, interdiction reportée à 2031
- Wallonie.be : nouveau régime de soutien à la rénovation énergétique au 1er octobre 2026
- Wallonie.be : régime temporaire des primes énergie (février 2025)
- Trustup : prix d'une installation de chaudière (mis à jour le 6 juillet 2026)
- Trustup : prix d'une chaudière au mazout
FUSE SERVICES operates in Brussels and both Brabants. Call the number shown at the top of this page for a quote.
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