Cost guides · United Kingdom

How much does a new boiler cost?

Published guides put a straightforward like for like combi swap, fully installed, at £1,800 to £4,500, and most converge on £2,200 to £3,000 for a standard 3 bed semi. Moving the boiler, changing boiler type or converting to a combi pushes the price materially higher.

£1,800–£4,500 fully installed for a like for like swap

The published figures

Every figure below is a published guide figure, shown as its publisher printed it and linked to the source. Retrieved on 2026-07-17.

WhatPublished figureBasisSource
Like for like boiler swap, fully installed£1,800–£4,500supply and installationCheckatrade cost guide (opens in new tab)
Combi boiler installation in a 3 bed semi£2,200–£2,800Checkatrade cost guide (opens in new tab)
Average combi boiler, supply and installaround £3,000Checkatrade cost guide (opens in new tab)
Conversion to a combi from a system or conventional boileraround £4,000supply and installationCheckatrade cost guide (opens in new tab)
Installation labour£500–£1,500labour onlyMyBuilder price guide (opens in new tab)
System power flush, as an add on£450–£800MyBuilder price guide (opens in new tab)
Fixed price combi to combi swapfrom £1,790fully installed, including flue, disposal and a smart thermostatBOXT fixed price installation (opens in new tab)

What moves the price

  • Boiler type: combi, system or conventional
  • Like for like swap versus relocating the boiler or converting the system
  • Property size and hot water demand: bedrooms, bathrooms, radiators
  • Brand and warranty length
  • Extras: new controls, radiators, a power flush

Get real quotes

Guide figures set expectations; only quotes set your price. Compare local businesses on their public evidence:

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Sources

Figures retrieved from the named sources above on 2026-07-17. Prices change; always confirm with quotes.