Boiler Installation Cost in London (2026): Real Fitted Prices
Quick summary: Most properly fitted boiler replacements in London cost £2,300–£4,800. The biggest price drivers are access and parking restrictions, system condition (cleaning/protection), gas pipe sizing, and whether you’re swapping like-for-like or doing a conversion/relocation.
How much does a new boiler cost installed in London? In 2026, a typical fitted replacement lands around £2,300–£4,800. If you’re specifically pricing a combi, see combi boiler installation prices and our breakdown of combi boiler cost for flats vs houses. The boiler unit is often £600–£4,000; a straightforward swap labour commonly sits around £1,000–£1,700. Totals move up when the system needs cleaning/protection, pipework or controls need upgrading, or the boiler type/location changes.
Typical fitted range (London): £2,300–£4,800 for a proper install. Costs are higher when you change boiler type, relocate it, upgrade an undersized gas pipe, or the system needs cleaning + protection.
Reality: many homes need at least one “extras” item (cleaning/protection, controls, minor upgrades). Exact needs depend on the property.
Want a fast, honest range for your exact place? Call 07727 154746.
| Cost item | Typical range | What changes it |
|---|---|---|
| Boiler (supply only) | £600 – £4,000 | Type, brand, output (kW), warranty length |
| Installation / fitting | £1,000 – £1,700 | Swap vs move, upgrades, access/parking, system condition |
| Total installed (common London range) | £2,300 – £4,800 | Complexity + what must be corrected to be safe & compliant |
Ready to get a quote fast?
If you send 4 quick photos we can usually give a tighter range quickly: boiler, pipework, flue, and controls. If you’re converting (system→combi etc.), include the hot water cylinder too.
- Accurate boiler quote checklist (fast)
- Boiler installation service hub (survey, fitting, commissioning & registration)
- Combi boiler installation prices
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Why London boiler installation prices are higher
London pricing isn’t “higher for no reason”. The same boiler model can cost more to fit because the install around it is often harder: flats, restricted access, parking rules, older housing stock, and compliance upgrades.
One of the biggest reasons quotes vary is the property itself — stairs/no lift, parking restrictions, awkward flue routes and cramped cupboards can add real time on site. If you want a realistic breakdown of boiler cost by property size, use that guide to sanity-check the range you’ve been given before you book.
- Access + time on site: tight cupboards, no lift, long carries, restricted working space.
- Parking/loading restrictions: paid bays, permits, short loading windows.
- Older housing stock: awkward flue/condensate routes, pipework layouts that need correcting.
- Compliance fixes: correcting unsafe/incorrect setups that “worked” but aren’t acceptable today.
- System condition: sludge/cold radiators/noisy pipework—cleaning + protection prevents early faults.
Comparing quotes? Read: why cheap boiler installation quotes fall apart in London.
Real London examples: these are the scenarios that usually swing the total (even when boiler brands look “similar”).
Example 1: 1-bed flat, combi replacement (same location)
- Work: remove + fit, commissioning, safety checks, register
- Often includes: cleaning/protection depending on system condition
Typical total installed: £2,300 – £3,000
If a quote is far under this, check what’s missing: costs people miss when getting a new boiler.
Example 2: 3-bed house, system → combi conversion
- Work: remove cylinder, pipework changes, controls setup, balance
Typical total installed: £3,200 – £4,500
More detail: combi installation prices.
Example 3: Relocation + gas pipe upgrade
- Work: move boiler, reroute flue/condensate, upgrade gas supply, make-good
Typical total installed: £4,000 – £5,200
Quote that doesn’t change later: how to get an accurate boiler quote.
Same-day / emergency replacement pricing (what actually happens)
- Emergency jobs are often “fast-track” surveys + parts + scheduling pressure.
- Totals rise if you need compliance upgrades, access is difficult, or parts have to be sourced same-day.
- Always confirm what’s included: cleaning/protection, controls, condensate route, and certification.
If you need urgent help, read: what urgent boiler replacement really costs.
What changes the total cost of a new boiler installed?
For budgeting, a typical London install clusters around £2,300–£4,800. What moves you up or down is usually system condition, access, and whether you’re doing a swap, conversion, or relocation.
- System condition: cleaning/protection prevents early faults.
- Gas supply: undersized pipes can limit boiler performance and sometimes need upgrading.
- Access/parking: flats, no lift, restricted access = more labour time.
- Boiler type change: conversions require more pipework and setup.
- Relocation: flue/condensate changes and making-good add time/materials.
If you’re already ready to book, start here: boiler installation in London.
Boiler type costs (installed): combi, system, regular
Below are realistic ranges for installed costs. Treat them as budgeting bands—your property and system condition determine where you land.
1) Combi boiler cost (installed)
| Combi boiler | Cost range | Notes |
|---|---|---|
| Boiler (supply only) | £600 – £4,000 | Brand, model, output, warranty |
| Installation labour | £1,000 – £1,700 | Higher with access issues or upgrades |
| Total installed | £1,600 – £5,700 | London often clusters £2,300–£3,800 for standard swaps |
Combi boilers suit many London flats and smaller homes. Costs rise when the gas supply is undersized, controls need upgrading, or the system needs cleaning/protection.
- No hot water cylinder (space-saving)
- Hot water on demand
- Often lower upfront install for suitable homes
- Can struggle with multiple bathrooms at once
- Relies on good mains pressure
- No stored hot water backup
Combi-specific breakdown: combi boiler installation prices.
2) System boiler cost (installed)
| System boiler | Cost range | Notes |
|---|---|---|
| Boiler (supply only) | £600 – £3,000 | Output and warranty change totals |
| Installation labour | £1,000 – £1,900 | Often more commissioning time |
| Total installed | £1,600 – £5,400 | London commonly £2,800–£4,500 depending on cylinder/controls |
System boilers store hot water in a cylinder. They can be a better fit for larger households or 2+ bathrooms, but need cylinder space.
3) Regular (heat-only) boiler cost (installed)
| Regular / heat-only boiler | Cost range | What to know |
|---|---|---|
| Boiler (supply only) | £600 – £3,500 | Often replaced like-for-like on existing systems |
| Installation labour | £1,000 – £2,000 | Older systems can require more work |
| Total installed | £1,600 – £5,800 | London commonly £2,900–£4,800 when older pipework needs attention |
Regular boilers are common in older properties. Like-for-like replacement can be sensible if the layout works, but older systems can add complexity.
Fuel type costs: gas, oil, electric, biomass
Boiler “type” (combi/system/regular) and “fuel” (gas/electric/oil) are different. Most London homes are gas.
Gas boiler prices installed
| Gas boiler cost | Typical range | Notes |
|---|---|---|
| New gas boiler (supply only) | £600 – £3,300 | Brand, output, warranty |
| Installation labour | £1,000 – £1,900 | Higher with upgrades/relocation |
| Total installed | £1,600 – £5,200 | London sits higher when access/compliance work is required |
Most cost swings aren’t the boiler unit — they’re the install: relocation, gas pipe sizing, cleaning/protection, controls and compliance.
Oil boiler cost (off-grid)
| Oil boiler cost | Typical range | Notes |
|---|---|---|
| New oil boiler (supply only) | £1,300 – £4,000 | Units are often higher than gas |
| Installation labour | £1,000 – £2,000 | Varies with flue/tank setup |
| Total installed | £2,300 – £6,000 | More common outside London |
Included for completeness—most London homes won’t need this.
Electric boiler cost (and why running cost matters)
| Electric boiler cost | Typical range | Notes |
|---|---|---|
| New electric boiler (supply only) | £500 – £3,000 | Purchase price can look similar |
| Installation labour | £900 – £1,900 | Depends on electrics/controls |
| Total installed | £1,400 – £4,900 | Running cost is the key decision |
Electric boilers can be neat and compact, but monthly bills matter more than installation day. We’ll usually talk through usage, insulation and alternatives before recommending one.
Biomass & specialist systems
Biomass and specialist systems can be significantly more expensive than standard gas installs. If you’re here to replace a gas boiler in London, focus on swaps, conversions, and extras.
Boiler conversion costs (system ↔ combi, regular ↔ combi)
Conversions cost more because you’re changing how the home stores and delivers hot water—more pipework, more controls, more commissioning.
| Conversion | Typical installed range | Why it costs more |
|---|---|---|
| Regular → Combi | £2,100 – £6,400 | Remove tanks/cylinder, pipework + controls changes |
| Regular → System | £2,500 – £7,400 | Storage setup + system alterations |
| System → Combi | £1,600 – £5,700 | Remove cylinder, rework hot water delivery, balance |
| Combi → System | £1,600 – £6,500 | Add cylinder, controls, space considerations |
Unsure what size/type you need? how to choose the right boiler size.
What actually changes the price of a boiler replacement?
Brands matter, but most of the final bill is driven by the same factors: access, system condition, and what must be upgraded to be safe and compliant.
- Property type & access: flats, tight cupboards, no lift, awkward carry routes.
- System condition: sludge, cold radiators, noisy pipework, repeated faults.
- Pipework & controls: undersized gas pipes, old valves, outdated controls.
- Relocation / routing: new pipe runs, flue/condensate changes, making-good.
- Compliance fixes: correcting unsafe/incorrect setups.
Compare quotes properly: why cheap boiler quotes fall apart in London.
New boiler costs by manufacturer (unit price ranges)
These are broad boiler unit ranges. Output (kW), model choice and warranty length matter.
| Manufacturer | Combi unit range | System unit range | Regular unit range |
|---|---|---|---|
| Worcester Bosch | £935 – £4,000 | £900 – £4,000 | £800 – £3,600 |
| Vaillant | £900 – £2,300 | £1,150 – £1,900 | £990 – £2,000 |
| Viessmann | £1,050 – £2,200 | £1,050 – £2,000 | £1,170 – £1,700 |
| Ideal | £1,040 – £1,770 | £1,295 – £1,700 | £1,200 – £2,960 |
| Alpha | £650 – £1,250 | £900 – £1,200 | £700 – £900 |
| Baxi | £660 – £1,500 | £900 – £1,500 | £900 – £1,550 |
Engineer note: a premium boiler won’t save a dirty system. Cleaning + protection often matters more than brand.
Common boiler installation extras (and typical costs)
When quotes “jump”, it’s usually because common extras weren’t included—especially in older London housing stock.
| Extra | Typical range | When it matters |
|---|---|---|
| Power flush / deep clean | £450 – £800 | Cold radiators, sludge, repeated faults |
| Magnetic filter | £100 – £300 | Protects the new boiler from system debris |
| Flue alterations | £200 – £700 | Relocation, compliance, awkward routing |
| Thermostatic controls / upgrades | £75 – £300+ | Better control + modern expectations |
| Gas pipe upgrade | £300 – £500+ | Undersized pipe starving the boiler |
Full breakdown: costs people miss when getting a new boiler.
Efficiency & realistic savings
Savings depend on what you’re replacing and how you heat your home. Replacing a very old boiler can reduce gas use noticeably; replacing a newer one that’s running well can be a smaller change.
Deciding between repair and replacement? repair vs replace (what’s cheaper long-term).
Government schemes & grants
Many “boiler scheme” searches are actually about low-carbon upgrades (like heat pumps) or targeted support through efficiency schemes. For a standard gas boiler replacement, support is usually limited unless you qualify under specific programmes.
Plain-English guide: boiler grants & government schemes explained.
FAQs (People also ask)
What is the average price of a new boiler and installation in London?
In London, a properly installed replacement commonly lands around £2,300–£4,800, depending on boiler type, access, system condition, and any upgrades needed.
How much is labour to fit a boiler?
For a straightforward like-for-like swap, labour is commonly £1,000–£1,700. It rises with relocation, upgrades, or cleaning/balancing work.
More detail: labour vs boiler cost.
How much does relocating a boiler cost?
Relocation can add hundreds because it means new pipe runs, flue and condensate changes, and making-good. Exact cost depends on distance and routing.
Can I get a grant for a new boiler?
For a standard gas boiler replacement, usually not. Most support is aimed at low-carbon heating or qualifying households under efficiency schemes.
Is it worth replacing a 15-year-old boiler?
Often yes—especially if it’s breaking down, losing pressure or repeatedly faulting. If faults keep returning, replacement usually wins long-term.
How do I get an accurate boiler quote quickly?
Send clear photos of the boiler, flue, pipework and controls, plus your property type and bathrooms. Ask if cleaning/protection is included so the price doesn’t change on the day.
Checklist: get an accurate boiler quote (fast).