- Like-for-like combi swap: £2,500–£4,000 supplied and fitted, usually in 4–6 hours (Checkatrade, October 2026).
- What people actually paid: a median of £2,500 for an emergency replacement and £3,000 for a planned one (Which? survey). Energy Saving Trust puts a typical gas boiler replacement at £3,500.
- Combi conversion or moving the boiler: about £4,000 for a conversion; moving it adds £600–£1,000 in labour.
- VAT is 20% on a gas boiler. The 0% energy-saving rate doesn't cover it, and the government-backed Warm Homes Loan won't fund one.
- Could you pay nothing? On a qualifying benefit, free boiler replacement through ECO4 may still be possible until 31 December 2026. Not guaranteed, so check your postcode.
Boiler quotes are hard to compare. One firm gives a single price, another splits the boiler, labour, flue and filter, and a third leads with a monthly payment. This guide breaks the new boiler cost into parts you can check against published prices. Every figure names its source and the date we checked it.
All prices are for gas boilers in Great Britain unless we say otherwise. They include VAT where the source says so. Your own quote depends on your home, so treat these as a benchmark, not a quote.
New boiler cost by type: combi, system and regular
The type of boiler sets the starting price. A combi heats water on demand and needs no tanks. A system boiler works with a hot water cylinder. A regular (heat-only or conventional) boiler uses a cylinder plus cold water tanks in the loft.
| Boiler type | Boiler only | Fitting | Typical total | Suits |
|---|---|---|---|---|
| Gas combi | £650–£3,000 | £1,000–£2,000 | £3,000 average | Flats and 1–3 bed homes, one bathroom |
| Gas system | about £1,500 | included in total | about £3,000 | Bigger homes, two or more bathrooms |
| Regular / heat-only | — | included in total | about £3,000 | Older homes with tanks, low water pressure |
| Oil combi | £2,500–£4,000 | £1,000–£2,000 | £4,000 average | Homes off the gas grid |
| Oil heat-only | £1,700–£4,500 | £1,000–£2,000 | £3,300 average | Off-grid homes with a cylinder |
| Electric boiler (12kW, no cylinder) | £1,200–£1,800 | £1,000–£2,000 | £3,000 average | Small homes and flats |
Source: Checkatrade new boiler cost guide, tables marked “last updated October 2026”, checked 30 October 2026. Checkatrade's figures are ballpark averages from its estimators. Engineers' labour averages about £300 a day.
So what does a combi boiler cost in practice? Checkatrade's overall range for a new boiler with fitting and typical extras is wide, at £3,000–£15,000, because it includes biomass and big conversion jobs. For an ordinary gas combi swap, the £2,500–£4,000 band is the one to benchmark against. Off the gas grid? An oil boiler is no longer your only option: see our oil boiler replacement grant guide for the £9,000 heat pump grant.
Boiler replacement cost by job
The biggest jumps in price come from changing what you have, not from the boiler itself. A straight swap in the same spot is always the cheapest boiler installation cost.
| Job | Typical cost | Time | Source |
|---|---|---|---|
| Like-for-like combi swap | £2,500–£4,000 supplied and fitted | 4–6 hours | Checkatrade |
| Regular to combi conversion | about £4,000 | 1.5–2 days | Checkatrade |
| System to combi conversion | about £4,000 | up to 3 days | Checkatrade |
| Back boiler to combi | about £4,000 | varies | Checkatrade |
| Moving the boiler (labour) | £600–£1,000 (about £800) | varies | Checkatrade moving guide |
| Pipework for a relocation | £400–£600 | — | Checkatrade gas pipe guide |
| New gas pipe run | £45–£85 per metre | — | Checkatrade gas pipe guide |
| Flue extension / bends | £75–£125 per metre | — | Checkatrade moving guide |
| Powerflush | from £400 (about 6 radiators) to about £1,000 | about a day | MyJobQuote; Checkatrade |
| Magnetic filter | £110–£310 fitted (see note) | — | Checkatrade; MyJobQuote |
| Wi-Fi / smart heating control | about £150 (supply only) | — | Checkatrade |
| Replacing a radiator | about £200 labour each | — | Checkatrade |
Sources, checked 30 October 2026: Checkatrade new boiler cost; Checkatrade cost of moving a boiler; Checkatrade gas pipe costs; MyJobQuote power flush cost 2026. The sources disagree on two items. Powerflush: MyJobQuote says from £400 for a smaller home, Checkatrade says about £1,000 including VAT. Magnetic filter: Checkatrade gives £60–£160 for the part plus £50–£150 to fit, and £150–£225 in its moving guide; MyJobQuote gives £180–£260 supplied and fitted. That's why we show a range.
New boiler cost: British Gas and other big installers
Search “new boiler cost British Gas” and you won't find a price list. British Gas gives a fixed-price quote after an online estimate or a free home visit, and says installation is always included in the price it quotes. Its finance examples show the kind of sums involved. Here's what the big names advertise. These are facts from their own sites, not a recommendation of any firm.
| Installer | What it advertises (checked 30 Oct 2026) | Worth knowing |
|---|---|---|
| British Gas | No list price. Finance example on its combi page uses a £2,503 cash price. Its “ways to pay” page uses £2,937, which it says is the average amount customers borrow. | Fixed-price quote online or after a home visit. Warranty needs a yearly service. |
| Boxt | “New boilers installed from £1,745” (like-for-like combi swap, same spot); boiler pages also say “supplied and fitted from as little as £1,760”. Changing a standard or system boiler to a combi “from £2,690”. | Online fixed price. “From” prices are the cheapest boiler on the simplest job. |
| Heatable | New boiler “from £1,845”. | Online fixed price; minimum spend applies to finance. |
| WarmZilla | Its own guide (updated October 2025) says installation prices “typically range from £1,500 to £4,000”. | Online fixed-price quote. |
Sources: British Gas combi boilers; British Gas ways to pay; British Gas new boilers; Boxt boilers; Boxt combi boilers; Heatable; WarmZilla installation prices. Advertised prices change often and promo codes come and go.
Online fixed-price firms are cheaper when your job is simple: same type, same spot, no extras. Once a survey finds a conversion, a new flue route or sludge in the system, the price rises. Always compare at least three quotes on the same specification.
Combi boiler prices by brand
Combi boilers prices vary by brand, range and output (kW). Which? publishes boiler-only price ranges for each range, from the smallest to the largest output. We show the main ranges below as plain facts, not a ranking. Fitting is extra.
| Brand | Combi range | Boiler-only price range | Standard / extended warranty |
|---|---|---|---|
| Ideal | i2 | £600–£846 | 5 / 5 years |
| Logic | £920–£1,170 | 7 / 7 years | |
| Logic Max | £1,160–£1,382 | 10 / 10 years | |
| Vogue Max | £1,379–£1,590 | 12 / 12 years | |
| Worcester Bosch | Greenstar 1000 | £704–£772 | 5 / 5 years |
| Greenstar 2000 | £851–£961 | 7 / 7 years | |
| Greenstar 4000 | £1,127–£1,274 | 7 / 10 years | |
| Greenstar 8000 | £1,510–£2,747 | 8 / 12 years | |
| Vaillant | ecoFIT pure | £2,044–£2,575 | 2 / 10 years |
| ecoTEC pro | £2,206–£2,558 | 5 / 10 years | |
| ecoTEC plus | £2,555–£3,808 | 5 / 10 years | |
| Viessmann | Vitodens 050-W | £934–£1,100 | 7 / 10 years |
| Vitodens 100-W | £1,230–£1,353 | 7 / 12 years |
Source: Which? brand reviews for Ideal, Worcester Bosch, Vaillant and Viessmann, checked 30 October 2026. These are boiler-only prices. Installers often buy below these figures, so a fitted price isn't simply boiler plus labour. Which? doesn't publish a free price table for Baxi, so ask installers to quote a Baxi model alongside others. Extended warranties usually need a registered, accredited installer and a yearly service.
Brand matters less than the fit. A well-sized mid-range boiler, installed properly with good controls, usually beats a premium model fitted badly. Ask each installer which model they'd fit, its output, and the warranty in writing. For more on choosing, see our boiler buying guide.
Running costs, efficiency and the Boiler Plus rules
A new boiler saves money when it replaces an old, inefficient one. In England, the Boiler Plus standards (in force since April 2018) set the minimum you can be sold:
- Every gas boiler fitted in an existing home must be at least 92% ErP efficient.
- New gas and oil boilers must come with time and temperature controls and boiler interlock.
- A new gas combi must also have at least one extra: flue gas heat recovery, weather compensation, load compensation, or smart controls with automation and optimisation.
Source: GOV.UK, Boiler Plus: initial policy review (BEIS, 2021). ErP is the EU-derived energy-related products efficiency rating used for boilers.
What could you save? Here's an illustration using the Ofgem price cap gas rate of 7.97p per kWh (1 October to 31 December 2026, Direct Debit) and a home that burns 9,500 kWh of gas a year in its old boiler, about Ofgem's typical medium use since July 2026.
| Old boiler efficiency | Gas a new 92% boiler would use | Gas saved a year | Saving a year (at 7.97p) |
|---|---|---|---|
| About 80% | 8,261 kWh | 1,239 kWh | about £99 |
| About 70% | 7,228 kWh | 2,272 kWh | about £181 |
Our arithmetic: gas saved = 9,500 × (1 − old efficiency ÷ 92%). Unit rate from Ofgem, which also cut its typical gas use figure by 17% in July 2026 (Ofgem press release). British Gas advertises a saving of up to £180 a year for a typical semi-detached home upgrading from a D-rated to an A-rated boiler, using lower gas prices. Real savings depend on your home and how you use the heating.
A new boiler won't transform a bill on its own. The saving is real but modest, so on cost alone the case is strongest when the old boiler is failing anyway. Lowering a combi's radiator flow temperature can help too: Which? reports a 6–8% gas saving from industry research.
VAT on a new boiler: 20%, not 0%
Heat pumps, solar panels, batteries and insulation get 0% VAT when installed in a home until 31 March 2027. Gas boilers don't. HMRC lists energy-efficient boilers as standard-rated, so a new gas boiler carries 20% VAT. Most advertised boiler prices already include it, but check the quote says “inc VAT”.
There's one narrow exception. A 5% rate applies to the grant-funded part of a gas or oil boiler or central heating installation in the main home of a qualifying person: someone aged 60 or over, or receiving certain benefits listed by HMRC. It only covers the part paid by a grant scheme aimed at low-income homes. See our 0% VAT relief guide for what does qualify for zero rate.
Source: HMRC VAT Notice 708/6, sections 2.23, 3.1–3.3, 3.8 and 3.9, checked 30 October 2026.
Paying for a new boiler: finance and the Warm Homes Loan
Gas boilers can't be paid for with a Warm Homes Loan. The government-backed Warm Homes Loan Scheme, live since 27 October 2026, only funds the measures listed in its rules. These include heat pumps, solar panels, batteries, heat network connections and micro-renewables. The rules say only measures explicitly listed are eligible, and gas boilers are not listed.
Sources: GOV.UK, Warm Homes Loan Scheme; DESNZ Warm Homes Loan Scheme rules, September 2026, sections 4.13–4.19.
Ordinary boiler finance is widely available. British Gas, Boxt and Heatable all advertise monthly payment plans, subject to status. When you compare, look at the total amount repayable, not just the monthly figure. Great British Energy does not arrange credit or recommend lenders.
If you'd rather borrow for a heat pump, a Warm Homes Loan can cover up to £20,000 of an air source heat pump before the grant is taken off, and it can be used alongside the Boiler Upgrade Scheme. Apply through a lender or an MCS installer. Full details in our Warm Homes Loan guide.
Get a boiler quote or check for a free boiler
Enter your postcode to see the free boiler funding you may qualify for, or ask for a quote from one accredited installer if you're paying. Free, no obligation.
Free boiler routes: who doesn't pay
Some households can get a new boiler without paying, or for a small top-up. These routes are narrow and funding is limited, so nothing is guaranteed.
- ECO4 (to 31 December 2026). Energy suppliers can still fund a replacement boiler for owners and private tenants on a qualifying means-tested benefit, where they still have funding. Ofgem confirms the scheme runs until 31 December 2026, and the government has said there will be no successor obligation. See our free boiler replacement guide and the ECO4 scheme guide.
- Pensioners. If you get Pension Credit, you may qualify through ECO4. Read boiler grants for pensioners, or if you don't get benefits, boiler grants for pensioners not on benefits.
- No central heating yet? Homes that have never had central heating may qualify for a first time central heating grant.
- Low income in England. The Warm Homes: Local Grant doesn't fund gas boilers, but it can fully fund a heat pump and insulation for eligible homes rated EPC D–G.
Not sure which applies? Our eligibility checker asks a few questions and tells you which routes fit your postcode and circumstances.
The heat pump alternative: £7,500 off (£9,000 for oil and LPG)
If your boiler needs replacing, it's the cheapest moment to look at a heat pump. The Boiler Upgrade Scheme gives £7,500 off an air source or ground source heat pump in England and Wales. Homes heated by oil or LPG with no mains gas get £9,000 until March 2027.
| Air source heat pump (Jul–Sep 2026) | Installed cost | After £7,500 grant | After £9,000 (oil/LPG) |
|---|---|---|---|
| Lower quartile | £10,717 | £3,217 | £1,717 |
| Median | £12,826 | £5,326 | £3,826 |
| Upper quartile | £15,461 | £7,961 | £6,461 |
Source: DESNZ Boiler Upgrade Scheme statistics, September 2026 (published 29 October 2026), table Q1.1A, reported installation costs of grants paid in Q3 2026. Grant amounts from GOV.UK. The “after grant” columns are our subtraction.
Running costs compared. Heat from 9,500 kWh of gas in a new 92% boiler is about 8,740 kWh. A heat pump with a seasonal efficiency (SCOP) of 3.0 would need about 2,913 kWh of electricity for the same heat: about £767 at the 26.32p price cap rate, against about £757 of gas. At a SCOP of 3.5, it's about £657. Going fully electric also drops the gas standing charge, about £108 a year at 29.68p a day. Heat pump tariffs can cut costs further. (Our arithmetic; SCOP figures are assumptions, and your MCS installer's estimate gives the real one.)
Next steps: heat pump cost UK, heat pump grants, heat pump vs gas boiler, or get a heat pump quote from one MCS-certified installer with the grant applied.
Repair or replace your boiler?
Not every fault means a new boiler. Checkatrade puts a typical boiler repair at £120–£750 for parts and labour, far less than a replacement. Replacing tends to make more sense when:
- the boiler is 10–15 years old or more (Checkatrade's typical lifespan);
- repairs keep coming back, or parts are getting hard to find;
- it's a non-condensing boiler. Energy Saving Trust says a metal flue usually means it isn't condensing, and a gas boiler fitted after 2005 should be;
- heating or hot water has become unreliable and bills are rising.
If it's still working, planning ahead gives you time to get proper quotes rather than taking the first price in an emergency. A yearly service costs about £80–£120 (Checkatrade) and keeps most warranties valid.
How to compare boiler quotes
- Check Gas Safe registration. By law, anyone working on gas in your home must be on the Gas Safe Register. Ask for their ID card, check the back lists boilers, and confirm the business on the Gas Safe Register.
- Get at least three quotes on the same spec. Energy Saving Trust recommends three and suggests TrustMark-registered installers.
- Ask for it itemised: boiler model and kW output, labour, flue, filter, flush, controls, removal of the old boiler and tanks.
- Check the controls meet Boiler Plus. On a combi, ask which of the four extras is included.
- Get the warranty in writing, with its service conditions, and who registers it.
- Ask for the Building Regulations certificate. In England and Wales the installer must notify the job through Gas Safe Register, and you should get a compliance certificate afterwards.
- Be wary of pressure. “Today only” discounts or big deposits before a survey are red flags.
Want to cut the cost before you sign? Check whether you qualify for a free boiler first, then weigh a new boiler against a heat pump quote with the £7,500 grant.