Updated 25 September 2026

Oil boiler replacement cost UK 2026

The going rate for oil boiler replacement in 2026 is £2,200–£5,500 (total, ex VAT). Below: a calculator, what the job involves, materials at three price levels, and the prep that changes the price.

Market band£2,200–£5,500
Worked example, 1 boiler£4,526
Time on site1 days

Oil boiler replacement calculator

Price a real job freeUses your rates, your speed and your receipts.

Market band source: MyJobQuote.

What the job involves

StageTaskTypical time
outDrain down and remove old boiler2 h
inFit oil boiler, flue and oil line8 h
inChemical cleanse, filter, inhibitor, commission2 h

Materials at three price levels

MaterialBudgetTrade choicePremium
Oil condensing boiler
each
£2,000
Internal oil combi or system — Like-for-like
£2,600
Branded oil boiler — Proven, parts available
£3,300
External weatherproof oil boiler — Frees space inside
Magnetic filter and cleanser
each
£90
Basic magnetic filter — Catches sludge
£130
Branded filter and cleanser — Protects the heat exchanger
£180
Dual-action filter — Best protection
Heating controls
each
£40
Wired programmable stat — Meets Part L controls
£80
Wireless programmable stat — Place it anywhere
£180
Smart thermostat — App control
Valves, pipe, fittings and condensate
allowance
£50
Standard fittings — Connects up
£80
Fittings plus frost-protected condensate — No frozen condensate
£120
Full copper tails and lagging — Tidy, efficient
Oil line, filter and fire valve
set
£90
Filter and fire valve — Required safety kit
£150
Plus de-aerator — Cleaner fuel supply
£220
Plus tank gauge — Know when to order

Trade prices ex VAT, estimates checked 2026-09-25. Log your receipts in Grafto and your own prices replace these.

What changes the price

Prep to look for

ConditionCheckEffect
Sludge in the systemblack water from a bleed valve, radiators cold at the bottomPower flush the system
Boiler age from badgedata badge or model label on the boilerCheck the boiler age on the badge: over 12–15 years, replace rather than repair
Possible asbestos laggingold grey or white pipe laggingPossible asbestos lagging: stop and test before disturbing

Questions

How much does oil boiler replacement cost in the UK in 2026?

The researched market band is £2,200–£5,500 (total, ex VAT), from MyJobQuote. A worked example of 1 boiler comes to about £3,506–£5,798 across budget, trade and premium materials.

How long does oil boiler replacement take?

The worked example of 1 boiler takes about 1 working days.

What changes the price of oil boiler replacement?

Mainly size and access, plus any prep found on site: sludge in the system, boiler age from badge, possible asbestos lagging.

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