How long does a gas safety certificate last?

A landlord gas safety record lasts 12 months. That is the short version, and it is the one most London letting agents quote. The detail matters more in a city where tenancies turn over fast and a flat in Hackney or Stratford can have three sets of tenants in two years. This guide explains the dates, the two month early window, and what records you have to keep.

The 12 month rule in plain English

Under regulation 36 of the Gas Safety (Installation and Use) Regulations 1998, a landlord must make sure every gas appliance and flue they provide is checked for safety every 12 months. The check must be done by a Gas Safe registered engineer. The HSE guidance on records sets out the paperwork side.

So the “certificate” is not valid for a year in the way a parking permit is. It is proof that a check happened on a certain date. The next check has to happen before that date comes round again.

What	The rule	Source
How often	Every 12 months, for each appliance and flue you provide	HSE, reg 36
Copy to current tenants	Within 28 days of the check	HSE
Copy to new tenants	Before they move in	HSE
Keep records	At least 2 years	HSE, reg 36(3)(c)
Early booking	Up to 2 months early, keeping the original deadline	HSE, reg 36A

The two month early window

Before 2018, booking a check early pulled your whole cycle forward. Book in month 10 and the next one was due a month sooner, every year after. Landlords with several flats lost weeks each year.

The Gas Safety (Installation and Use) (Amendment) Regulations 2018 changed that. You can now have the check done in months 11 or 12 and keep the original deadline date, as if the check had been done exactly 12 months after the last one. HSE calls this regulation 36A.

There is a catch. To use the window, you must be able to show you met the timescales. HSE says the record then has to be kept until two further gas safety checks have been carried out. In practice that means keeping three years of records, not two.

Why the dates drift in London

London has a lot of rented homes. In the 2021 Census, 38.5% of households in Newham and 38.2% in Tower Hamlets rented privately, against 20.5% across England (ONS, Newham, ONS, Tower Hamlets). Camden and Haringey were both at 35.6%.

High turnover is where dates slip. A tenant moves out in August. The flat is empty for three weeks. The agent books a check to cover the new let, then forgets the old one is still due in November. Two checks a few months apart, with no clear record of which date counts.

Getting access is the other common problem. In converted Victorian houses in Stoke Newington or Kentish Town, the boiler for the top flat might be in a kitchen cupboard, and the meter for all three flats in a shared hall or basement. If one tenant cannot be in, the whole visit can fail. HSE expects you to show repeated, reasonable attempts to get in, and to keep the letters and notes.

A new appliance changes the dates

If you fit a new boiler or gas fire part way through the year, that appliance needs its first safety check within 12 months of being installed. HSE allows a one off flexibility here too. You can stretch the gap between installation and first check by up to two months, so the new appliance lines up with the rest of the property. It can only be used once for each new appliance (HSE, what if).

The new boiler will also come with a Building Regulations Compliance Certificate. That is a different document. It shows the installation was notified to the council, not that the property has had its annual safety check.

What happens if the record is out of date

An expired record means the landlord has not met the legal duty for that period. It cannot be fixed by backdating. A record shows the date the engineer actually did the check, with their name, registration number and signature. Anything else is not a valid record.

If you find your record has lapsed:

1. Book the check now and explain it is overdue.
2. Give the tenants a copy within 28 days of the new check.
3. Keep a note of why it lapsed and what you did.
4. Set reminders for months 10 and 11 next time.

If you are letting through a licensing scheme, producing the record to the council each year is a mandatory licence condition under the Housing Act 2004. Our post on property licensing in Newham and Waltham Forest covers how councils ask for it.

Electronic copies are fine

HSE says you can keep and send records electronically, as long as they can be printed when asked, are secure, and identify the engineer who did the work. You can email a tenant their copy if they are happy with that, but you must give a paper copy if they ask. In shared houses, a copy can be displayed in a prominent place, as long as tenants are told where it is and how to get their own.

Booking the next check

The simplest habit is to book the next check at the end of this one, inside months 11 or 12 of the new cycle. That keeps the deadline fixed and gives you a cushion if a tenant has to rearrange.

London Gas Engineers can arrange a landlord gas safety certificate for flats and houses across north and east London. Whoever you use, ask to see their Gas Safe ID card and check the back lists the appliances in your property. A boiler, a hob and a gas fire are separate work categories.