How much does a new boiler cost in Surrey and South West London? (2026 guide)

If your boiler is old, unreliable or getting expensive to repair, the next question is what a replacement will cost. Prices vary more than most people expect, so this guide explains the typical ranges in 2026 and what actually changes the price.

Typical 2026 prices

Industry price guides for 2026 (Heatable) give these typical installed costs across the UK:

• Like-for-like combi boiler swap: around £1,800 to £3,500, usually fitted in about a day.

• System or conventional boiler replacement: around £1,800 to £3,500, usually one to two days.

• Converting a conventional or system boiler to a combi: around £3,000 to £5,700, because tanks, cylinders and pipework change.

Labour in London and the South East is generally higher than in other regions. Our own new boiler installations start from £3,200, with a written quote after a survey.

What pushes the price up

• Changing boiler type or moving the boiler to a new position.

• A new flue route, especially vertical flues through a roof.

• Old or undersized pipework that needs upgrading.

• Boiler output and brand: larger homes need more power, and premium brands with longer warranties cost more.

• Extras such as smart thermostats, weather compensation, extra radiators or a new hot water cylinder.

What should be included

A proper installation is more than the boiler. When you compare quotes, check that each one includes:

• The exact boiler model and its warranty length.

• A system clean or flush, and a magnetic filter on the return pipework.

• The flue kit, condensate pipe and any frost protection it needs.

• Controls, and whether they are compatible with weather or load compensation.

• Registration of the installation with Gas Safe and the manufacturer, so your warranty is valid.

If a quote is much cheaper than the others, it usually leaves out one of these.

Repair or replace?

As a rough guide, it is worth considering replacement if your boiler is more than 12 to 15 years old, breaks down regularly, uses a discontinued part, or your heating bills keep rising. An engineer can check the efficiency and condition before you decide.

Get a quote

The Essential Connection fits and services boilers across Walton-on-Thames, Weybridge, Cobham, Esher, Kingston, Wimbledon, Fulham and Chelsea. All gas work is carried out by Gas Safe registered engineers. Book a survey or ask a question, or call 07719 664615.