Landlord Certificates
How Often Do You Actually Need A Gas Safety Certificate?
Reviewed by our Gas Safe registered engineers · Last updated 22 July 2026
The short answer is every 12 months — but exactly when within that window matters more than most landlords realise. Get it wrong and you can either lose your renewal date or end up with a gap in cover.
Quick answer: renew between 10 and 12 months after your last check to keep the same annual date going forward. Renewing earlier than 10 months resets your anniversary date to the new, earlier one. Once the 12 months has passed there’s no grace period — you’re non-compliant until a new check is done.
Engineer Advice
The 10–12 month window explained
Your certificate is valid for exactly 12 months from the date of issue. To avoid any gap while keeping your original renewal date, the check needs to happen within the 10 to 12 month window after the previous one — sometimes called the ‘concessionary period’. Renew within that window and your new certificate’s 12-month countdown effectively continues on the same annual schedule.
Renew earlier than 10 months (say, at 8 months) and your new anniversary date shifts to that earlier point — not a problem in itself, but it does move your renewal schedule going forward.
| When you renew | Effect on your renewal date |
|---|---|
| 10–12 months after last check | Keeps your original annual date going forward |
| Earlier than 10 months | Resets your anniversary to the new, earlier date |
| After 12 months (lapsed) | No grace period — non-compliant until a new check is done |
Real-World Example
A common scenario we see
A landlord in Enfield had their check done every January without fail. One year, worried about being ‘too late’, they booked it in October instead — nearly three months early. That reset their renewal date to October going forward. Not a disaster, but it meant remembering a new date and that year’s check happened noticeably sooner than needed. Booking within the window keeps things predictable year on year.
If You've Missed It
If you've missed your deadline
Treat it as urgent
If your certificate has already lapsed, book a check as soon as possible — there’s no grace period once the 12 months has passed. Continuing to let the property without a valid certificate is a legal breach with potentially serious consequences, so treat it as urgent rather than routine.
Getting back on track
Once a new check is done you’re compliant again, and the fresh certificate sets a new 12-month schedule from that date. Send us your details and we’ll get an engineer out quickly — often the same day, subject to availability.
Costs
What renewing within the window costs
Renewing within the 10–12 month window costs the same as any standard annual check — there’s no premium for timing it correctly. The only real cost of poor timing is administrative: tracking a shifted renewal date going forward.
Typical North London guide prices — you’ll always get an upfront quote before any work starts. Same-day or emergency requests may carry a small callout supplement depending on availability.
FAQs
Timing and renewal — your questions answered
What happens the very first time a property is let — when does the 12 months start?
From the date of the first check carried out before or at the start of the first tenancy. All appliances and pipework need to be checked and safe before a property is first let.
Can I set a reminder through Koncore so I don't have to track the date myself?
Yes — we can set up an automatic reminder ahead of your renewal window so you’re prompted with plenty of time to book, without needing to track it manually.
Does moving to a new letting agent reset or affect my renewal date?
No. The renewal date is tied to the property’s certificate history, not to who’s managing it, so changing agents doesn’t affect your existing schedule.
If I sell the property, does the certificate transfer to the new owner?
The certificate relates to the property’s condition at the time of the check and can be provided to a new owner for reference, but they’ll need to establish their own ongoing renewal schedule as the new legal duty holder.
Is there flexibility if my usual engineer is unavailable near my renewal date?
As long as the check happens within the 10–12 month window, it doesn’t need to be the same engineer or company each year, so booking an alternative is entirely fine if your usual provider isn’t available.
Do all appliances need re-checking every year, even ones rarely used?
Yes. Every gas appliance and all pipework needs checking at each annual visit regardless of how often it’s used, since the safety check covers the installation’s condition, not usage patterns.
How far in advance can I book my renewal to make sure it falls within the window?
Most landlords find it easiest to book a few weeks ahead of the earliest date in their window, giving flexibility for an engineer’s availability without risking slipping past the 12-month mark. Booking too far ahead risks landing before the 10-month point — which is why marking the whole window in your calendar, not just a single date, is worth doing.
Does the 10–12 month window apply to every gas appliance, or just boilers?
It applies to the property’s gas safety check as a whole, which covers every gas appliance and all pipework together in a single visit, rather than each appliance having its own separate renewal timing. It’s one reason to have everything checked at the same visit rather than piecemeal.
Related
Related guides
What a CP12 is and what it covers.
Read guideLandlord CertificatesLandlord Gas Safety DutiesThe full legal checklist beyond the check itself.
Read guideLandlord CertificatesEICR vs Gas Safety CertificateThe two checks landlords confuse.
Read guideMaintenanceAnnual Boiler ServiceA service is not the same as a safety check.
Read guideMaintenanceSigns Your Boiler Needs ServicingSpotting problems between checks.
Read guideEmergencyCarbon Monoxide Warning SignsThe safety risk behind the checks.
Read guideBrowse all Landlord Certificate guides, or head back to the Help & Advice Centre.
Not sure when yours is due?
Send us your last certificate and we’ll confirm your renewal window — then set a reminder so it never slips. Gas Safe registered, North London, upfront pricing.
Gas Safe Registered 918817 | North London specialists | Upfront pricing