Oil boilers
An oil boiler burns heating oil from a tank outside the house. It is the usual choice in rural homes with no mains gas, and a modern condensing oil boiler is far more efficient than an old one.
Who oil boilers suit
Suits
- Rural homes with no mains gas
- Properties with an existing oil tank
- Homes where an oil supply is already in place
Good points
- Works where there is no mains gas
- Condensing models cut oil use compared with old boilers
- Fuel is delivered, so there is no gas connection to pay for
Watch out for
- Needs an oil tank and a delivery contract
- Oil prices change, and so do running costs
- More servicing than a gas boiler
What oil boilers cost
Oil boilers typically cost £3,300 (Oil boiler, heat-only at the low end and combi at the high end, fitted), with most jobs between £2,700 and £6,000. That includes VAT at 20%. Fitting takes 1–3 days on site.
What you would actually pay
Typical Oil boiler, heat-only at the low end and combi at the high end, fitted · UK- Typical installed cost Oil boilers, supplied and fitted
- £2,750
- VAT at 20% Standard rate
- £550
- Net cost to you
- £3,300
If you borrowed £3,300.00 over 36 months at 0.0%, it would cost £91.67 a month – £3,300.00 in total, of which £0.00 is interest. The last payment would be £91.55.
Illustration only – not a quote, not an offer of credit, and not financial advice. Rates depend on your circumstances and creditworthiness.
Where the money goes on oil boilers
| Element | Typical range |
|---|---|
| Boiler and fitting A new oil boiler fitted to the existing tank and pipework. A heat-only boiler sits at the lower end of the range and an oil combi at the upper end. This row is the headline price. | £2,700 – £6,000 |
| Power flush Cleaning the radiators and pipework before the new boiler goes on. Optional, and worth asking about on an old system. | £400 – £1,000 |
| Magnetic filter Catches the iron sludge that wears out a boiler, and many manufacturers ask for one under their warranty terms. | £110 – £310 |
Guide prices including VAT. Your actual cost depends on your home, access and specification.
What moves the price of oil boilers
- The boiler itself
Budget ranges cost the least, mid-range ranges sit in the middle, and premium ranges with longer warranties cost the most. Output matters less to the price than the range does.
- Like for like or a conversion
Swapping a boiler for the same type in the same place is the cheapest job. Changing type, moving the boiler or re-routing the flue adds pipework, labour and days.
- The state of the system
Old radiators and pipes full of sludge can need a power flush, new valves or a filter before the installer will fit a new boiler under warranty.
- Where you live
Installer rates are higher in London and the South East than in the North and in Scotland, and the regional pages show the difference.
- Who fits it
National installers and local Gas Safe engineers quote differently for the same boiler. Compare quotes on the make and model, the warranty and what is included, not on the headline price alone.
What a quote for oil boilers should include
If a quote is missing any of these, ask why before you compare it with another.
- The make, model and output of the boiler, and the length of the manufacturer warranty once it is registered
- Whether the price includes a magnetic filter, a system clean or flush, and the cost if the installer finds the system needs one
- Whether the flue, the condensate pipe and any new pipework are included, and what a longer or relocated flue adds
- Removal and disposal of the old boiler, and who registers the installation with Gas Safe and the manufacturer
- A fixed price in writing, the deposit and the payment schedule, and the workmanship guarantee
- The date, the number of engineers and how many days the heating and hot water will be off
Oil boilers prices by region
Labour is most of the difference. Typical price (Oil boiler, heat-only at the low end and combi at the high end, fitted), including VAT.
| Region | Typical | vs UK average |
|---|---|---|
| London | £4,100 | +25% |
| South East | £3,900 | +17% |
| South West | £3,600 | +10% |
| East of England | £3,500 | +6% |
| West Midlands | £3,400 | +4% |
| Scotland | £3,400 | +2% |
| East Midlands | £3,300 | UK average |
| Yorkshire and the Humber | £3,300 | UK average |
| North West | £3,200 | −2% |
| North East | £3,100 | −5% |
| Wales | £3,100 | −6% |
| Northern Ireland | £2,900 | −12% |
Common questions about oil boilers
Is an oil boiler cheaper than gas?
It depends on the price of oil against the price of gas, and many oil homes have no gas to compare. The boiler costs more to fit, and the fuel is bought in bulk.
Can I get a grant to replace an oil boiler?
The Boiler Upgrade Scheme pays towards a heat pump in homes off the gas grid in England and Wales. It does not pay for a new oil boiler. Check the scheme page for current eligibility.
Should I choose an oil combi?
An oil combi saves the cylinder, but it costs more and the output needed to heat water on demand makes the boiler bigger. A heat-only oil boiler with a cylinder is the usual choice for larger homes.
Is VAT charged on a new gas boiler?
Yes. Gas boilers are standard-rated, so the price shown includes VAT. The zero rate for energy-saving materials applies to heat pumps, solar panels and insulation, not to gas boilers.
Where these oil boilers prices come from
Guide prices are compiled from published UK price guides, converted to a price before VAT, and shown here with VAT added. They are indicative, not quotations. How we price explains the method.
Get quotes for your home
A guide price only takes you so far. Local firms can price the work on your own home, and comparing a few quotes is the quickest way to see what is reasonable.
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