How to Track Gas Safety Certificate Renewals Across a Growing Customer Book (2026)
A spreadsheet or memory tracks renewals for twenty or thirty customers. Past that, a real system needs one view of every due date, a lead-time window and a record you can hand over on request.
Updated 6 October 2026
TLDR: A business can track twenty or thirty customers’ renewal dates from memory or a spreadsheet tab. Past that, a real system needs one place that shows every customer’s next due date, a lead-time window that fires before it lapses, and a per-customer record you can hand a landlord or an inspector on request.
A one-van gas engineer with two dozen regular customers can carry most of their renewal dates in their head, backed up by a wall calendar or a spreadsheet tab. It is not elegant, but it works, because the whole list fits in view at once.
Somewhere past that size, the maths changes. A hundred and fifty customers on a roughly annual cycle means a due date lands almost every working day of the year. That duty is not limited to buy-to-let landlords either: HSE’s guidance on who needs a gas safety check lists housing associations, local authorities, hostels, colleges and boarding schools alongside private landlords, so a trade firm’s renewal-cycle customers are usually wider than its residential landlords alone. A flat list stops being something anyone checks; it becomes a file opened once, for the customer who already rang to chase their own booking.
Why manual tracking breaks down as your book grows
What happens if a landlord’s renewal is missed?
A gas safety check for a landlord has a real deadline attached to it, not a loose target. Under Regulation 36 of the Gas Safety (Installation and Use) Regulations 1998, a landlord must have every gas appliance and flue checked within 12 months of installation and at intervals of no more than 12 months after that; HSE’s Approved Code of Practice L56 sets out the detailed guidance behind that duty for landlords and engineers alike. A 2018 amendment lets the check happen up to two months early and still keep the original 12-month anniversary, which is why many engineers work to a ten to twelve month window rather than waiting for the deadline itself. Working in Northern Ireland rather than Great Britain? The same annual-check duty sits in Regulation 36 of the Gas Safety (Installation and Use) Regulations (Northern Ireland) 2004, so the tracking problem does not stop at the border.
Miss that window and the cost is not abstract. Shelter England sets out the consequences plainly: the Health and Safety Executive can serve an improvement or prohibition notice and can prosecute the landlord or the letting agent, a local authority can act on housing conditions, and a landlord who has not handed over a current record cannot serve a valid Section 21 “no fault” eviction notice, under the Assured Shorthold Tenancy Notices and Prescribed Requirements (England) Regulations 2015. The government’s own How to rent checklist, which an assured-shorthold landlord in England must hand every tenant, tells that tenant to expect a copy of the gas safety certificate before they move in and again after each annual check, so a landlord who cannot produce one is visibly short of a document their own tenant was told to look for. None of that lands on the engineer directly, but a customer who finds out their compliance lapsed because nobody chased the booking is not a customer who rebooks. HSE’s own guidance on what to keep sets the record at two years from the check date, longer still if an early check under the 2018 amendment means two further checks have to pass first.
What does manual tracking cost as the book grows?
The admin cost scales with the book even before a single renewal is missed. Say a firm carries 180 active customers on roughly annual cycles and checks each one by hand: finding the row, confirming the date, then phoning or texting to chase the booking. Four minutes a customer, a reasonable estimate for that lookup, comes to 720 minutes, 12 hours, a year, before counting the ones that get missed first time and need a second chase. At the National Living Wage rate of £12.71 an hour from April 2026, used here only as a statutory floor, that is roughly £152 a year in paid time just finding and chasing dates a system would have surfaced on its own. Change the customer count, the minutes per lookup or the rate to match a real business; the point is that manual tracking’s cost grows in a straight line with the book, while a system’s does not.
What a renewal-tracking system needs to do
Four things separate a system that holds up at scale from a list that quietly stops working:
- A single view of every customer’s next due date. Not one date per open job tab, but a list sorted by what is coming due soonest, across the whole book.
- A lead-time window that fires before the date, not on it. A landlord’s gas safety record needs more notice than a boiler service a homeowner can rebook the same week.
- A per-customer history that survives the person who remembers it leaving. If a renewal date or a past certificate only lives in one person’s head or inbox, the book has a single point of failure.
- An export a landlord or an inspector can be shown. Handing over a clean record, rather than promising to “check and get back to you,” is part of what the tracking is for.
How to set up renewal tracking across a growing book
The order matters more than the tool. Work through these in sequence:
- List every active customer with a renewal-type job, and the date of their last completed check. A gap here is where a missed renewal usually starts, not at the reminder stage.
- Set a lead time per job type, not one default for everything. A landlord gas safety record, an EICR, a PAT test and a boiler service do not carry the same urgency.
- Pick a channel to match the relationship. Email suits a landlord or letting agent who checks it daily; SMS or a printed letter reaches a residential customer who does not.
- Decide where a confirmed rebooking lands. A reminder that gets a reply but no diary slot has only done half its job.
- Export or back up the full list on a schedule. A record that only exists inside one piece of software disappears if you ever change systems.
Where does Checker fit into this?
What does the Annual Service Reminder actually do?
Our Annual Service Reminder, one of four automated workflows under Automations, reads the due date on a job’s file and sends one message before it expires. The lead time is set per file type, anywhere from one to twelve weeks before the file is due, with a four-week default, so a landlord gas safety record can run on a longer lead time than a boiler service. Reminders go out by email, SMS or a branded letter you print and post, replies land in your own inbox or phone rather than inside Checker, and every reminder also lands on your diary, so a confirmed rebooking turns straight into a job.
The customer database behind it lets you search any name, postcode or part of an address and pull up that customer’s full job, certificate and invoice history in one place, and the whole list exports to CSV at any time, with every job, certificate and invoice attached.
Which plan actually includes it?
Said plainly, since it changes which plan answers the tracking problem: the customer database, the Annual Service Reminder and the online dashboard sit on our PRO and PRO+ plans. LITE covers invoicing, quotes and job sheets, but carries no CRM, reminders or accounts sync, so tracking across a growing book needs PRO or PRO+, not LITE.
A reminder prompts a booking. It does not carry out the check or issue the certificate; that part of the job is still yours.
| Approach | What it actually tracks | Where it tends to break down | What it costs |
|---|---|---|---|
| Memory or a spreadsheet | A flat list of names and dates, updated by hand after each job | Holds up to roughly 20 to 30 active customers; past that, the list only gets opened once a customer calls | Free, until a missed renewal costs a booking or an HSE notice |
| Checker | Every customer’s next due date, set per file type, with one configurable lead-time window | Sits on PRO and PRO+; LITE does not include it | PRO from £19.99 a month, PRO+ from £25.99 a month, both plus VAT |
| A standalone reminder or texting app bolted onto your current tools | A one-off reminder message, set manually against a job | No link back to the certificate or invoice, so the lead time and the paperwork live apart | Varies by provider; check whether it reads your job records or needs its own separate list |
| A full job-management platform built around scheduling and invoicing, with reminders as one feature among many | Reminders alongside quoting, scheduling and invoicing in one account | Can be the right call when several things need rebuilding at once, not when reminders are the one gap in an otherwise working setup | Typically a higher monthly price than a reminder-only tool, reflecting the wider feature set |
Approach: Memory or a spreadsheet
What it actually tracks: A flat list of names and dates, updated by hand after each job
Where it tends to break down: Holds up to roughly 20 to 30 active customers; past that, the list only gets opened once a customer calls
What it costs: Free, until a missed renewal costs a booking or an HSE notice
Approach: Checker
What it actually tracks: Every customer’s next due date, set per file type, with one configurable lead-time window
Where it tends to break down: Sits on PRO and PRO+; LITE does not include it
What it costs: PRO from £19.99 a month, PRO+ from £25.99 a month, both plus VAT
Approach: A standalone reminder or texting app bolted onto your current tools
What it actually tracks: A one-off reminder message, set manually against a job
Where it tends to break down: No link back to the certificate or invoice, so the lead time and the paperwork live apart
What it costs: Varies by provider; check whether it reads your job records or needs its own separate list
Approach: A full job-management platform built around scheduling and invoicing, with reminders as one feature among many
What it actually tracks: Reminders alongside quoting, scheduling and invoicing in one account
Where it tends to break down: Can be the right call when several things need rebuilding at once, not when reminders are the one gap in an otherwise working setup
What it costs: Typically a higher monthly price than a reminder-only tool, reflecting the wider feature set
See your own customer list against a due-date view and a lead-time window before you commit to anything. Get Started Free
Frequently asked questions
How many customers before a spreadsheet stops working?
There is no fixed number, but most one and two person firms find it starts slipping past 20 to 30 active customers on a renewal cycle, once dates no longer fit on one screen.
Can I set a different lead time for different job types?
Yes. Our Annual Service Reminder lead time is set per file type, from one to twelve weeks before the file is due, so a landlord gas safety record can run on a longer lead time than a boiler service if that fits how you work.
Does a missed reminder mean a customer’s compliance has already lapsed?
Not necessarily, but it removes the warning that would have let you rebook before the deadline. A reminder prompts the booking; it does not perform the check or decide whether a property is compliant.
Which Checker plan includes the renewal dashboard and reminders?
PRO and PRO+. The customer database, the Annual Service Reminder and the online dashboard are not part of LITE, which covers invoicing, quotes and job sheets without a CRM or reminders.
What happens to my renewal records if I switch software later?
Check this with any provider before you commit to tracking renewals inside it. Our own customer list exports to CSV at any time, with every job, certificate and invoice attached, so the record does not depend on staying on one piece of software.
Check your renewal tracking before it breaks
Before the next busy month, check your own setup against this list:
- Can you see every customer’s next due date in one place, sorted by what is coming soonest?
- Does each job type have its own lead-time window, rather than one default for everything?
- Would a renewal still get chased if the person who usually remembers it was off sick?
- Could you export the full list today, if a landlord customer asked for their record?
If any answer is no, that is the specific gap worth closing first, not a sign the whole system needs replacing.
Further reading
Authoritative sources
- Checker Automations: quote, invoice and service chasers
- Checker service reminders
- Checker customer database (CRM)
- Checker diary and job scheduling
- Checker current pricing
- Checker homepage
- UK Trade Certificates and Records to Track in 2026
- How to Set Up Automated Service Reminders for UK Gas, Heating and Electrical Work
- Gas Safety (Installation and Use) Regulations 1998, Regulation 36
- HSE: Approved Code of Practice L56, Gas Safety (Installation and Use) Regulations 1998
- HSE: gas safety FAQs for landlords and letting agents
- Gas Safety (Installation and Use) Regulations (Northern Ireland) 2004, Regulation 36
- Assured Shorthold Tenancy Notices and Prescribed Requirements (England) Regulations 2015, Regulation 2
- GOV.UK: How to rent, the checklist for renting in England
- HSE: gas safety check records and what to keep
- HSE: gas safety checks, who needs them
- Shelter England: gas safety in rented homes
- GOV.UK: National Minimum and Living Wage rates