Boiler service cost UK 2026: what you should pay

A boiler service is one of the cheapest things you can do for your heating, and one of the easiest to get wrong by paying for a job that was not really done. A one-off gas boiler service costs £80 to £120 in 2026, with the national average close to £100. London and the South East add £20 to £40. That price buys the engineer’s time and a set of safety and performance checks. It does not cover repairs.

The number matters less than what you get for it. A rushed 15-minute visit and a proper 40-minute service can carry the same price tag. This guide covers both.

Points to take away

• Budget £80 to £120 for a one-off gas boiler service, more in London and for oil or LPG.
• A real service takes 30 to 45 minutes, with the casing off and a flue gas analyser reading.
• Under 20 minutes with the casing left on is not a full service, whatever the invoice says.
• An annual service keeps a new boiler’s warranty valid. Keep the paperwork.
• Cover plans suit older or less reliable boilers. A reliable newer boiler is usually cheaper to service standalone.

Reading time: about 6 minutes.

What a boiler service costs in 2026

Prices below are typical UK figures for a standalone service, not part of a cover plan. Add £20 to £40 for London and the South East.

Very cheap offers, £45 to £55, are common in autumn. Some are a genuine loss-leader from a good firm. Others are a quick visual check dressed up as a service. Ask what is included before you book.

What a proper service includes

A full service is more than a look and a wipe. The engineer should:

• Check the boiler fires and runs correctly, and note any fault history
• Remove the casing and inspect the burner, heat exchanger, and electrodes for wear, corrosion or debris
• Check the flue and its seals, inside and outside
• Take a flue gas analyser (FGA) reading to confirm combustion is safe and efficient, and record the figures
• Check gas pressure and the gas rate
• Check the condensate trap and pipe
• Check system pressure and the expansion vessel
• Test safety devices
• Complete and stamp the service record in your Benchmark logbook

The FGA reading is the part that separates a service from a glance. It is the only way to confirm the boiler is burning cleanly and not producing carbon monoxide. If the engineer never connects an analyser to the flue, you did not get a full service.

Signs of a rushed or fake service

• The visit takes under 20 minutes
• The casing never comes off
• No flue gas analyser is used
• Nothing is written in your Benchmark book or a service certificate
• You are quoted for “repairs” you cannot see and that were not there before

A good engineer will show you the FGA figures and tell you plainly whether anything needs watching. If a manufacturer later disputes a warranty claim, your stamped service records are the evidence that saves you.

Does my warranty need an annual service?

Almost always, yes. Manufacturers offering 7, 10 or 12-year warranties make them conditional on a service every 12 months by a Gas Safe registered engineer, with the record kept. Miss a year and the warranty can be void even if the fault is unrelated.

Keep every service certificate and the stamped Benchmark logbook. When you sell the house, that history also reassures a buyer and their surveyor. If your boiler is getting to the age where a warranty claim is likely, our guide to the signs a boiler needs replacing is worth a read before you spend on major repairs.

Cover plan or pay as you go?

A boiler cover plan bundles the annual service with repair cover, for £100 to £250 a year depending on the excess and what is included.

The maths is simple. If your boiler is under about eight years old and has not faulted, a standalone service at £100 a year plus the occasional repair usually costs less over five years than five years of cover premiums. You are effectively self-insuring.

Cover earns its place when: the boiler is older and likely to fault, a sudden £400 repair would be a real problem, or you want the certainty of a fixed monthly cost. Read the exclusions closely. Many plans do not cover a boiler over a certain age, pre-existing faults, or the full cost of a replacement.

Booking a service

Book in late summer or early autumn, before the first cold snap fills every engineer’s diary. Have your boiler make, model and age ready, and ask the engineer to confirm the service includes an FGA reading and a completed service record.

Get free quotes from Gas Safe registered engineers covering your postcode, or browse the directory to find heating companies registered in your area.