Gas Safety Certificate Expiry Calculator
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A landlord gas safety check has to be repeated at least every 12 months. You can have it done up to two months before the deadline and still keep the original date. Enter your date below to see your next deadline and the earliest day you can renew.
When is my next gas safety check due?
It depends on the date of the last check that counts. As of October 2026, regulation 36 of the Gas Safety (Installation and Use) Regulations 1998 requires each appliance and flue covered by that duty to be checked at intervals of not more than 12 months. Regulation 36A lets you check in the two months before the deadline and still keep that deadline. Enter the last check date and this page shows the due date and a reminder suggestion. The sums run in your browser. Nothing you type is sent to us.
How the two-month window works
You can have your landlord gas safety check done in the two months before your deadline and it still counts as done on the deadline date. So with a 12 April deadline, a check on any day from 12 February to 12 April keeps your renewal date at 12 April the following year. Book earlier than that and the 12 months restarts from the day of the check.
Why use the deadline, not the visit date
If you renew early, your next deadline is the old deadline plus 12 months. The date on the certificate shows when the engineer visited, so it's easy to count from the wrong date. If you only have the visit date and it was an early check, tick the box above and add the previous deadline.
What else you need to do
Use a Gas Safe registered engineer. Give existing tenants a copy of the record within 28 days and new tenants a copy before they move in. Keep your copy until two further checks have been done. For the full rules, read our gas safety certificate guide for landlords. Gas, EICR and EPC dates together are on the certificate due-date calculator. A tick-list that stays in this browser is the landlord compliance checklist. The 12-month rule on its own is in how often landlords need a gas safety check.
Keep every certificate in one place
Calendar reminders fall over the moment two properties have different dates. Gaffy keeps each property's certificates together and emails you 90, 30 and 7 days before the expiry date you save, then once that date has passed. You book the engineer. As of October 2026, Gaffy is free for the first month, with no card needed to start, then £12 a month for up to 5 properties, plus £4 a month for each additional property. The rule itself is on the gas safety certificate reminder page. The same dates can sit in the landlord certificate tracker, next to the EICR, EPC and deposit documents.
Start free for 1 monthGas safety expiry FAQs
How long is a gas safety certificate valid for?
A landlord gas safety check must be repeated at least every 12 months. The certificate itself doesn't expire on a printed date, so what matters is the deadline for your next check, which this calculator works out.
How early can I renew my gas safety certificate?
Up to two months before the deadline. A check done in that window counts as done on the deadline date, so your next deadline stays 12 months after the original one rather than moving forward.
What happens if I renew more than two months early?
It's treated as a normal check, so your next deadline becomes 12 months from the day it was done. You aren't breaking the rules, but you'd lose the months between that check and your old deadline.
Do I have to give my tenant the new gas safety record?
Yes. Existing tenants must receive a copy within 28 days of the check, and new tenants must receive the latest record before they move in.
When should I be reminded about the next gas safety check?
Book inside the two months before the deadline if you want to keep the date. If you save the gas safety record in Gaffy with that expiry date, the emails go out 90 days, 30 days and 7 days before it, and once the date has passed.
General information, not legal advice. This tool applies the 12-month rule in regulation 36 and the two-month early window in regulation 36A of the Gas Safety (Installation and Use) Regulations 1998. Check your engineer's record and HSE guidance for your situation.