Once a year. An annual boiler service by a Gas Safe registered engineer keeps your boiler safe and efficient, and is usually required to keep the manufacturer’s warranty valid. Here is what a service involves, what happens if you skip it, and the best time to book.
How often should a boiler be serviced?
Annually. Manufacturers design boilers around a yearly service, and it is the single best way to catch small problems before they become expensive breakdowns. For landlords it dovetails with the legal annual gas safety check, though the two are different things.
What happens if you do not service your boiler?
- It costs more to run. A poorly maintained boiler burns more gas for the same heat.
- More breakdowns. Minor faults that a service would catch turn into mid-winter failures.
- Safety risk. An unserviced boiler is more likely to develop faults that can produce carbon monoxide — a gas you cannot see or smell.
- Warranty problems. Many manufacturers require proof of annual servicing; skip it and a future claim may be refused.
What is actually checked in a service?
A proper service is more than a glance. We inspect the main components, check the boiler is burning correctly and at the right gas pressure, check the flue and ventilation, look for leaks and corrosion, clean key parts where needed, and finish with a written record of what was done. See our boiler service page for the full breakdown.
Does servicing keep my warranty valid?
In most cases, yes. Manufacturers generally require an annual service by a Gas Safe registered engineer as a condition of the warranty, and we provide a record you can keep as proof.
When is the best time to book?
Autumn is ideal — get it done before you are relying on the heating every day, so any issue is found before the cold sets in rather than during it. That said, a service any time of year is better than none.
Frequently asked questions
Is a boiler service a legal requirement?
For homeowners, no — but it is strongly recommended and often a warranty condition. Landlords are not required to service annually but must keep appliances safe and to manufacturer requirements, so an annual service is the practical way to meet that.
How long does a service take?
A standard service is usually completed within about an hour, depending on the boiler and its condition.
Can you do a service and a landlord certificate together?
Yes. If you need both, tell us when you book and we will carry them out in one visit — handy for landlords needing a CP12.
About the author: J. Ahmed is the founder of Gas First Ltd and a Gas Safe registered engineer (587401), working across East London since 2016.