Gas safety certificate software: a UK guide

Last updated: August 2026

It is Thursday and the record for Flat 4 expired on Tuesday. You had not forgotten it: it was in the spreadsheet, in the September tab, and then a no heat callout ate the morning and the tenant did not answer the door anyway. The agent has now emailed asking for it, which means the agent has noticed. That is the part that costs money.

A landlord gas round is not really a jobs business. It is a list of properties with anniversary dates attached, and the only thing that generates next year’s revenue is that list being right. The craft is 30 to 60 minutes. The business is date keeping.

A round is a list of dates, not a list of jobs

Three shapes of business run this work: the sole trader with 300 to 700 properties on the books; the firm of two to eight, usually built by winning an agent contract and then hiring to service it, which is where one person’s memory stops holding the round; and the compliance contractor working for housing associations and councils.

The customer base is split down the middle. There were 4.7 million households in the private rented sector in England in 2024 to 2025, 19% of all households, and the social sector adds several million more under the same duty. In 2024, 43% of English landlords used agent letting services while 52% used no agent at all, and 85% of individual landlords hold one to four properties. So a round is a very large number of very small customers plus a few agents who each bring dozens.

The list itself usually lives in one of four places, each failing in its own way. A wall planner, which cannot be searched. A spreadsheet sorted by expiry date and filtered to the next 60 days, which works until there are two engineers in the van. Google Calendar with yearly recurring events, the worst of them, because a recurrence set to the visit date walks the anniversary backwards every time a check is done early. And a WhatsApp group with the agent, where access is actually negotiated and none of it is recorded.

All four accumulate ghosts: a property sold, a boiler removed, a tenant switched to electric. Once the list is not trusted the round stops being worked proactively, the agent notices the late certificate, and the property goes to somebody else.

The deadline date, and the rule your reminders should key off

Regulation 36(3)(a) requires each appliance and flue to be checked at intervals of not more than 12 months since it was last checked. Read alone, that means an early check permanently costs the landlord those days, and doing it every year walks the anniversary backwards through the calendar.

Since 6 April 2018 it has not meant that. Regulation 36A provides that a check completed within the two months ending with the deadline date is treated as having been made on the deadline date. The deadline date is the term of art: the last day of the 12 month period within which the check was required.

Two things about it matter operationally and are almost never said. First, it is a deeming provision, not an automatic one. Somebody has to record the next due date against the deadline date. If your software dates the renewal 12 months from the visit, the landlord quietly loses the window every year and the anniversary drifts anyway.

And there is a second, separate discretion in regulation 36A that is not the same rule at all. A landlord may have an appliance checked up to two months late, but only once for each appliance or flue, and only to align its deadline date with that of another appliance in the same premises. It exists so a boiler fitted in March and a fire fitted in July come onto one visit. Calling it two months of leeway would be dangerous advice.

Regulation 36A also extends to England, Wales and Scotland only. Northern Ireland’s 2004 regulations keep the unamended structure, so treat that flexibility as unestablished there.

The record, who gets it, and how long you keep it

The document is legally a record, not a certificate, and CP12 is a form number left over from the registration regime that ended in 2009. Regulation 36 lists nine items it must contain, two of which cause real friction. The landlord’s name and address is mandatory, with the agent’s details permitted where appropriate, so a managed portfolio where nobody will disclose the landlord leaves you holding a document arguably non compliant on its face. And only safety defects have to be recorded: Technical Bulletin 055 puts that as ID and At Risk defects, so best practice observations do not belong there, where an agent cannot tell a legal failure from a suggestion.

Then delivery, where the engineer gets blamed for somebody else’s deadline. A copy goes to each existing tenant within 28 days of the check, and to any new tenant before they occupy. The 28 days runs from the check, not from the day you invoiced, so a week of typing up documents in the evening has eaten a quarter of the landlord’s window. Handing it over on move in day does not satisfy a pre occupation duty.

Retention is where nearly all published content is wrong. In Great Britain the rule has not been two years since 2018: the record is kept until there have been two further checks of that appliance or flue, or, if it is removed, for two years from the last check. Northern Ireland still says two years. They usually coincide, but not when the early window is used repeatedly or a check is late. HSE on gas safety records confirms electronic records are fine, provided they reproduce in hard copy, are secure from loss and interference, and uniquely identify the engineer.

No access, and who actually carries the cost

The duty is the landlord’s. The person standing at a door at 9:40 on a Tuesday is you.

HSE on dealing with tenants sets out what reasonable steps look like: the tenancy should allow access, but force must never be used; leave a notice saying an attempt was made; write to the tenant explaining that the check is a legal requirement and is for their safety; offer them the chance to book it themselves. HSE’s landlord FAQ puts a number on repeated attempts, at least three, and HSE strongly advises keeping a record of all correspondence. Ultimately a court decides whether what was done was reasonable.

The ceiling on that escalation is now clear. In Southern Housing v Emmanuel, decided at Bromley County Court in November 2025, the judge held that no judge can give a landlord permission to force entry into a tenant’s home, because any power to enter forcibly must come from express statutory authority. Injunction, contempt and possession are the ladder, and there is no shortcut. It is a county court decision, persuasive rather than binding, but it is the clearest recent statement available. The Housing Ombudsman has separately faulted one landlord for leaving a property without a valid record for 11 months while pursuing access.

The practical problem is whose phone the evidence sits on. The date, the time, the card left, the message sent: all created at the door and, in most businesses, never leaving the handset. A no access visit costs the whole slot and often earns nothing, and whether it is chargeable is contractual, so agree it in advance.

What the round is worth, and what an agent costs you

The visit is priced per property, not per hour, and the floor is public: certificate only operators advertise from £40. Bundling with a boiler service is the standard answer, typically saving the landlord £20 to £40 against buying both separately, with extra appliances adding £10 to £15 each.

Density decides whether the round pays. A check is 30 to 60 minutes on site, so a well planned day is six to eight properties and a day of scattered singles across a city might be four. That is the whole margin, and batching geographically within an expiry month is the core skill here.

Agents fix the density problem and create three others: terms of 30 to 60 days against a same day cost base; remittances batching forty invoices into one payment, with deductions, reconciled line by line; and contractor onboarding refreshed annually. If most of your work arrives that way, working for letting agents covers the shape of it.

On tax this round sits in a friendlier place than general heating work. HMRC’s own manual says the legislation refers only to the installation of building service systems, so repairs and part replacement fall outside CIS, and with them the VAT domestic reverse charge, which never reaches an end user anyway. That changes the moment you also install as a subcontractor to a main contractor: check your position with your accountant, and see boiler repair and installation as a business.

Two thresholds to watch: VAT registration at £90,000, where crossing effectively raises every price 20% against unregistered rivals, and Making Tax Digital for Income Tax, which has applied since 6 April 2026 above £50,000 of qualifying income and drops to £30,000 in April 2027 and £20,000 in April 2028.

How Dispatch helps

Dispatch runs the round around the certificate: the properties, the access, the visits and the money, so the only thing left in your gas software is the record itself.

Recurring visits, switched on in Settings, raise the annual visit as a repeat rather than something anyone has to remember. The map view clusters jobs and does radius search, which is the batching problem solved: twelve properties in one postcode district become one day rather than four. Two way chat with photographs, opened from a link you send by WhatsApp or text, puts the access conversation with the tenant on the job where the office can see it.

Cancelling forces a written reason with a timestamp and the person who recorded it, which is a far better no access record than a missed call and a memory. Certificates you produce attach to the job and are kept for its life, so a request to re-issue one from four years ago takes seconds.

Your Gas Safe number prints on every invoice and quote you issue. You enter it once in Settings, under Invoicing, and Dispatch carries it onto the paperwork from then on — a landlord’s agent checking that the engineer who signed the record is registered does not have to ask. It is frozen onto each document as it is issued, so renewing or changing your number never rewrites paperwork you have already sent.

Then invoice the landlord or the agent, take card payment into your own Stripe account, and let overdue invoices chase themselves at 3, 10 and 21 days in your name.

Every feature is on every plan, the caps are on seats and templates only, everything runs in the UK, and there is a free plan to try it on next month’s batch.