New Boiler Cost UK 2026: Combi, System & Regular Prices Compared
A new boiler is one of the biggest one-off bills most UK homes ever face. This guide breaks down 2026 prices by type, brand and size, lays bare the hidden extras that inflate quotes, and shows you the real lifetime cost so you can decide whether to replace, repair or take out cover.
Quick answer
A new boiler in the UK typically costs £1,800–£4,500 fully installed in 2026. A standard like-for-like combi swap usually lands at £2,300–£3,000 — early-2026 quote data puts the median UK combi quote at around £2,300. Budget jobs can start near £1,500, while complex installs, premium brands or system conversions can pass £6,000.
Roughly half the bill is the boiler unit and half is labour, plus any "hidden extras" such as a power flush, flue work or relocation. These are indicative figures — always confirm the price on a Gas Safe registered engineer's written quote.
How much does a new boiler cost in the UK in 2026?
A new boiler in the UK costs roughly £1,800 to £4,500 fully installed in 2026, including the unit, parts and a Gas Safe registered engineer's labour.
For the most common job — a like-for-like combi replacement — expect £2,300 to £3,000. Quote data from early 2026 puts the median UK combi quote at around £2,300, with most standard swaps landing between £2,150 and £3,000.
The full range runs from about £1,500 for a budget swap to £6,000 or more for a complex install, premium brand or a change of boiler type. Where you fall depends on the type, the brand, the size you need and any extras.
This guide is information, not financial or gas-safety advice. The cheapest quote on the day isn't always the cheapest boiler to own — warranty length, annual running cost and out-of-warranty repair bills all matter, and we cover the true lifetime cost further down. Any installation, sizing or repair decision should be made with a Gas Safe registered engineer.
New boiler cost by type
The single biggest price driver is the type of boiler. Combis are cheapest because there are no separate tanks or cylinders; system and regular boilers cost more because they involve extra components and longer installs.
| Boiler type | Unit only | Installed (typical) |
|---|---|---|
| Combi | £700–£1,800 | £1,800–£4,000 |
| System (+ cylinder) | £800–£2,000 | £2,500–£5,000 |
| Regular / conventional (+ tanks) | £700–£2,500 | £2,200–£5,500 |
| Electric | — | £1,700–£4,500 |
| Oil | — | £2,500–£7,000 |
| Back-boiler conversion | — | £3,000–£6,000 |
| Biomass | — | £10,000–£18,000 |
A system boiler adds a hot-water cylinder (£500–£1,000) plus more labour (£1,000–£2,000). A regular boiler keeps a cylinder and the loft tanks, with labour up to £2,500 on a like-for-like job.
Changing type — say a regular system to a combi — costs more than a straight swap because pipework, the cylinder and tanks all change. See our full boiler replacement cost guide for a deeper breakdown.
New boiler cost by brand
Brand matters for both the unit price and the warranty you get. Premium brands cost more up front but back it with longer guarantees; budget brands are cheaper but typically carry shorter warranties.
| Brand | Unit only (supply) | Tier |
|---|---|---|
| Worcester Bosch | £1,000–£2,500 | Premium |
| Vaillant | £1,000–£2,000 | Premium |
| Viessmann | £900–£2,200 | Premium |
| Ideal | £700–£1,800 | Mid |
| Baxi | £850–£1,500 | Mid |
| Alpha | £600–£1,200 | Budget |
| Glow-worm | £600–£1,200 | Budget |
| Potterton | £600–£1,100 | Budget |
A premium Worcester Bosch or Viessmann can carry a 10–12 year guarantee when fitted by an accredited installer and registered — often worth the extra outlay if you plan to stay put. (Vaillant typically offers up to 10 years via its Advance installer scheme.) For more on which brands hold up, see our guides to the most reliable boiler brands and the best combi boilers for 2026.
What size boiler do I need?
Boilers are rated in kilowatts (kW). Too small and you'll run out of hot water; too big and you waste gas and money. Sizing is set by your number of bathrooms, radiators and hot-water demand — not by floor area alone.
| Combi output | Suits |
|---|---|
| 24–27 kW | Flat or small terrace, up to ~10 radiators, 1 bathroom |
| 28–30 kW | 3-bed semi (the most common UK size, around 30 kW) |
| 32–35 kW+ | Larger 4+ bed home, 2 bathrooms |
System and regular boilers are sized by cylinder capacity and a heat-loss calculation rather than flow rate. A Gas Safe registered engineer should carry out a proper heat-loss assessment before recommending an output — get this in writing, as an oversized boiler is a common upselling tactic.
What's in the price — labour & installation breakdown
Labour is typically 40–50% of the total. A Gas Safe registered engineer's day rate runs £300–£600 a day, and a standard like-for-like swap takes one day (about 4–8 hours).
- Labour: usually 1 day for a straight swap; longer for conversions or relocations.
- Sundry materials: £100–£500 (valves, fittings, flue parts, filter).
- Certification: Building Regs / Benchmark certificate and Gas Safe notification — should be included as standard.
Gas work — the gas supply, burner, flue and sealed combustion side of any boiler — must legally be carried out by a Gas Safe registered engineer; it is never a DIY job. If a quote omits the certificate or registration, treat that as a red flag — these aren't optional extras. If you ever smell gas or suspect a leak, call the National Gas Emergency line on 0800 111 999.
Hidden extras that push the price up
This is where two quotes for "the same boiler" can differ by £1,000. Many installer pages bury these. Here's the checklist competitors tend to skip — ask your engineer which apply to you.
| Extra | Indicative cost |
|---|---|
| Boiler relocation | £300–£800 |
| Flue extension or reroute | £75–£400 |
| Power flush | £300–£750 |
| Magnetic system filter | £50–£200 |
| Pipework upgrades (e.g. gas supply, 22mm) | £200–£500 |
| Old / back-boiler & asbestos removal | Varies — specialist if asbestos |
| Waste / old-boiler disposal | £50–£150 |
Converting a regular system to a combi adds significantly because of pipework and removing the cylinder and tanks. A new condensate run may also be needed where one doesn't exist. See our guide to power flush prices to judge whether that line item is fair.
Cost by boiler swap scenario
Worked examples make the ranges concrete. These are illustrative 2026 figures for a 3-bed home with a mid-range brand:
- Like-for-like combi swap (same spot): ~£2,300–£3,000. The cheapest scenario — minimal pipework.
- Combi swap with a power flush + filter: ~£2,800–£3,600. Common where the system is sludgy.
- Regular → combi conversion: ~£3,500–£5,000. Removing the cylinder and tanks plus new pipework drives the jump.
- Relocation (e.g. airing cupboard to kitchen): add £300–£800 plus flue and pipe runs.
Regional price variation
Where you live changes the bill, mostly through labour rates. London and the South East are dearest; the North, Wales and Scotland tend to be cheaper.
The gap can be 15–25% on the same job. It's one reason getting three local quotes is worth the effort — national fixed-price installers don't always reflect your local rate.
Grants & ways to cut the cost in 2026
First, an honest myth-bust: there is no government grant for a new gas boiler in 2026. The headline schemes are for low-carbon heating, not gas.
- Boiler Upgrade Scheme (BUS): £7,500 towards an air- or ground-source heat pump, or £5,000 towards an eligible biomass boiler — not gas boilers. The heat-pump grant is open to homeowners in England and Wales regardless of income; biomass is restricted to off-gas-grid, rural properties. The scheme currently runs to 31 March 2028.
- ECO4: support for low-income and vulnerable households, currently running to 31 December 2026. Eligibility is means-tested and funding is limited, so apply early.
Scheme rules and end dates change — this is information, not advice, so check your eligibility on the official Ofgem and GOV.UK pages before relying on any grant. To cut the cost of a gas boiler itself: get three quotes, consider off-peak install months (spring/summer demand is lower), and compare fixed-price online installers against premium nationals like British Gas. See our explainer on the Boiler Upgrade Scheme if a heat pump is on your radar.
New boiler finance
Most large installers offer finance, often 0% interest-free or buy-now-pay-later, spread over 2–10 years. As a rough illustration, a £2,400 boiler over 3 years at 0% is around £67 a month.
- Pros: spreads a big bill; 0% deals mean no extra cost if you keep up payments.
- Cons: longer interest-bearing terms add up; you're tied to one installer; you may pay more than shopping around with cash.
Always check the APR and total repayable before signing. Credit is subject to status and affordability checks. This is general information, not financial advice — whether finance suits you depends on your own circumstances.
Is it worth replacing — or should you repair or get cover?
A new A-rated boiler can cut running costs sharply against an old G-rated one. Energy Saving Trust estimates put the typical annual saving from replacing an old G-rated gas boiler (with new controls) at roughly £150–£640, depending on the property:
- Detached house: up to ~£640/yr
- Semi-detached: ~£385/yr
- Bungalow: ~£345/yr
- Mid-terrace: ~£320/yr
- Flat: ~£150/yr
Savings vary with energy prices and your home, so treat these as indicative rather than guaranteed. A useful rule of thumb: replace if your boiler is 8–10+ years old, or if a single repair is creeping toward 50% of a replacement. Below that, repairing is often the smarter spend — see our guides on whether to repair or replace your boiler and typical boiler repair costs.
If your boiler is sound but out of warranty, boiler cover can cap your exposure to surprise breakdowns. We weigh that up in whether boiler cover is worth it, and you can compare boiler cover from our selected panel of providers (not the whole market). Note that some plans are FCA-regulated insurance while others are unregulated service or care plans — check which you're buying. Disclosure: we may earn a commission if you take out cover through links on this site, at no extra cost to you. This never affects the prices you pay or our editorial assessments.
Total cost of ownership — the real number
The sticker price is just the start. The figure that actually matters is what the boiler costs over its 10–15 year life. Competitors rarely add this up; we will.
| Cost element | Typical |
|---|---|
| Purchase + install (one-off) | £2,300–£3,000 |
| Annual service | £80–£120/yr |
| Running cost (gas) | Varies — A-rated saves £150–£640/yr vs G-rated |
| Warranty (in-period) or boiler cover (after) | Warranty up to 10–12 yrs premium; cover from a few £/month |
Over a boiler's life, the annual service and any cover can add up to more than the install itself — but they protect the asset and keep efficiency (and your warranty) intact. Budget for a yearly service: our annual boiler service costs guide has the going rates. Viewed this way, a slightly dearer, longer-warranty boiler often wins on lifetime cost.
What's the cheapest boiler type to install?
A combi boiler is usually the cheapest to install, typically £1,800–£4,000, because there's no separate hot-water cylinder or loft tanks to fit. A like-for-like combi swap in the same position is the lowest-cost job of all.
How long does a new boiler installation take?
A standard like-for-like swap takes about one working day (roughly 4–8 hours). Conversions — such as moving from a regular system to a combi — or relocating the boiler can take two days or more. All gas work must be done by a Gas Safe registered engineer.
How long should a boiler last?
A well-maintained boiler typically lasts 10–15 years. An annual service helps it reach the upper end and usually keeps the manufacturer's warranty valid. Once past 10 years and out of warranty, repair-versus-replace maths starts to favour a new unit.
Are there any grants for a new gas boiler?
No. In 2026 there is no government grant for a new gas boiler. The Boiler Upgrade Scheme gives £7,500 toward a heat pump (or £5,000 for an eligible off-grid biomass boiler), not gas boilers, and currently runs to 31 March 2028. ECO4 supports low-income households but is means-tested. This is information, not advice — check eligibility on the official Ofgem and GOV.UK scheme pages.
Can I spread the cost of a new boiler?
Yes. Many installers offer finance, often 0% interest-free or pay-later plans over 2–10 years. Always check the APR and total repayable, as longer interest-bearing terms cost more overall. Credit is subject to status. This is general information, not financial advice.
How much more does a system boiler cost than a combi?
A system boiler usually costs more because it needs a hot-water cylinder (£500–£1,000) and extra labour. Installed, combis run roughly £1,800–£4,000 and system boilers £2,500–£5,000 — so expect to pay several hundred pounds more for a system setup.
Do I need a power flush with a new boiler?
Not always. A power flush (£300–£750) clears sludge from older systems and many manufacturers require the system to be clean for the warranty to stand. On a newer or already-clean system, a chemical flush plus a magnetic filter may be enough. Ask your Gas Safe registered engineer to justify it before agreeing.
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Compare boiler & central heating cover from a selected panel of UK providers and find a plan that fits your boiler and budget. Information, not advice — we show a chosen panel, not the whole market.
Compare boiler coverThis article is general information, not financial or gas-safety advice. We compare a selected panel of providers, not the whole market, and may earn a commission if you buy through our links. Always have gas appliances checked and repaired by a Gas Safe registered engineer; in a gas emergency call 0800 111 999. Prices are indicative UK guides for 2026 — confirm current prices on the provider's own site.