What to charge
Supplied and fitted prices include the boiler and labour, and Heatable's figures include VAT.
Labour only£550–£9004 to 6 hours on site, boiler supplied by the customer
Combi swap, supplied and fitted£1,800–£3,500one day on site, boiler and labour
System boiler swap, supplied and fitted£1,700–£4,000one day on site, boiler and labour
Day rates by region
- UK average: £200 to £435 per day
What moves the price
Boiler outputBigger boilers cost more to buy, so the total rises with kW.
FlueA vertical flue usually costs extra.
PipeworkOld lead or unusual pipework needs extra work.
CylinderA new cylinder on a system swap adds £350 to £750 vented or £900 to £1,400 unvented.
System conditionA heavily sludged system needs a power flush rather than a chemical flush.
LocationLondon jobs cost noticeably more than the same job in the north.
Materials
Combi boiler, supply only£525–£2,300
System boiler, supply only£500–£1,700
Magnetic filter, fitted£180–£260
How long it takes
A same-position swap takes 4 to 6 hours, so one working day.
Questions
What should I charge in labour for a like-for-like swap?
Labour only runs £550 to £900 for a boiler swap in the same position.
How long does a like-for-like swap take?
A same-position swap takes 4 to 6 hours, so one working day.
What is the typical quoted price for a combi swap?
Heatable's median quote for a standard combi replacement was £2,300, from 2,000 quotes between January and May 2026.
What should I charge for a power flush?
MyJobQuote puts a 3-bed power flush at £470 to £520, and Which? gives an average of £500.
What if the customer wants the boiler moved?
It is no longer like-for-like. Labour for a relocation runs £850 to £1,300 and takes 1 to 2 days.