How much does it cost to replace an oil boiler in the UK?
Check the steps below first — if you're not confident, get it fixed safely today.
Post a job — we'll find you an engineer →Oil boiler installation must be carried out by an OFTEC-registered technician.
Not sure if this matches your problem?
Use our interactive tool — answer a few questions and get a personalised diagnosis.
Most likely cause & what to check
A new oil boiler supply and installation costs £2,000–£4,000 for a standard replacement. Popular brands include Grant, Worcester Bosch (Greenstar Oil), Firebird, and Warmflow. An OFTEC-registered technician is legally required for oil boiler installation.
The cost is higher than gas boiler replacement due to more complex flue and oil supply connections. Oil boilers are typically floor-standing (larger than wall-hung gas combis) and require appropriate siting near the oil supply.
Oil tank considerations: if your tank is over 15–20 years old, or if it is single-skin steel (rather than bunded — double-walled), replacing it at the same time as the boiler is strongly recommended. A new bunded plastic tank costs £600–£1,500 including installation. An oil spill is costly to remediate and can result in Environment Agency liability.
Annual oil consumption for an average UK home is 1,500–2,500 litres. At current oil prices (around 65–80p/litre), annual fuel costs are £975–£2,000. This compares to gas costs of £600–£1,200 for a similar home — oil is typically more expensive to run.
Future-proofing: properties on oil heating are likely candidates for heat pump conversion, especially as the oil boiler ban (currently proposed for off-gas-grid homes in new builds) may extend to existing properties. The BUS grant (£7,500 for ASHP) applies to oil-heated homes too.
OFTEC registration: always use an OFTEC-registered technician. Verify at oftec.org. Unregistered work on oil heating is illegal and may invalidate insurance.
This job needs a qualified engineer — post it now
Post the job and we'll match you with vetted local engineers. Free, no obligation.
Was this guide helpful?