Most CP12s get written up in the van, from memory, an hour after the boiler was switched off. Readings drift. Landlords chase. The paperwork eats the engineer's own time, not the job's. There is a better way to produce a gas safety record, and it does not involve learning yet another app.
Guide · Gas
CP12 software options for gas engineers.
Gas Safe engineers have more options than ever for producing CP12 records, from paper pads to dedicated apps to WhatsApp workflows. An honest comparison for engineers and firm directors.
Free forever: 20 reports a month. No card, no trial clock.
The problem
Most CP12s are completed in the van.
Readings are taken at the property and transferred to the form afterwards from memory, introducing transcription errors. An engineer doing 6-8 properties a day faces over an hour of admin off their own time. Then landlords and agents chase for copies nobody planned to retrieve.
The options
Four ways to produce a CP12.
Paper
Legal, low volume
Legally valid and familiar, but records cannot be searched and there is no reminder system. Wrong answer for a growing portfolio.
GES & CorgiDedicated gas tools
Gas Engineer Software is the most widely used purpose-built platform. A monthly fee for each engineer suits small firms but does not cover other workflow types.
iAuditorCapable, generic
Handles CP12 records but is not purpose-built for gas. Per-seat pricing climbs steeply; justified around 40+ staff with diverse workflows.
WhatsApp workflow
How Quickler captures a CP12.
- 1
Answer on site
Questions arrive in WhatsApp during the job. The engineer replies by text or voice note. Voice notes are transcribed automatically, capturing readings in real time.
- 2
Certificate generates
On completion the certificate generates from the collected data. One-click email sends the PDF to the landlord or agent, who can also be given read-only dashboard access.
Get started
CP12s completed during the job, not after.
No CP12 software is approved by Gas Safe; the record content is what matters. £20 per active user per month with a £20 monthly minimum, plus a free tier of 20 reports a month, extra dormant users always free. Only pay for who works, dormant users free.
The short version
- Paper CP12 forms are still legal and still used, but they mean certificates completed from memory in the van, with no searchable archive.
- Gas Engineer Software (GES) is the most widely used dedicated tool; a monthly fee for each engineer suits small firms.
- iAuditor can handle CP12 records but is not purpose-built for gas; its template depth is the strength.
- WhatsApp-based platforms let engineers voice note readings on site, then the certificate generates from the transcript.
- No CP12 software is approved by Gas Safe. The record content is what matters legally.
The problem
The CP12 gets written in the van.
Most UK gas engineers do the check, make notes, and finish the certificate afterwards. The readings, gas rate, operating pressure and flue gas analysis are taken at the property and transferred to the form outside it. That breaks in two places.
First, accuracy. Readings copied from memory twenty minutes later carry transcription errors. The engineer knows they were fine. The record may not say so precisely.
Second, volume. Six to eight properties a day means six to eight certificates. At ten to fifteen minutes each, that is over an hour of admin at the end of a full day, off the engineer's personal time. Most firms accept this as the cost of doing business. It is not.
Option one
Paper: legal, simple, and a trap at scale.
Paper CP12 forms come from Gas Safe Register and various suppliers. Every required field is there. They are legally valid. For a sole trader doing two or three landlord gas checks a week, paper works fine.
The problems arrive with scale. Paper records cannot be searched. When a letting agent asks for the gas safety record on a specific flat from eleven months ago, finding it means leafing through a folder, or worse, realising the only copy was left with the landlord. There is no reminder system either. Track forty annual checks and you are tracking due dates by hand: no dashboard, no overdue flag, no alert. Paper suits low volume and absolute simplicity. It is the wrong answer for a growing portfolio across multiple engineers.
Option two
GES and Corgi HomePlan: built for gas.
Gas Engineer Software is the most widely used dedicated platform for UK gas engineers. It produces properly formatted CP12 records, handles EICR and boiler service records, and stores everything in a searchable cloud archive. The interface was designed for gas work, not adapted from a generic inspection tool.
It charges a monthly fee for each engineer, running at £20 to £40 depending on tier. Comfortable for a firm of five to ten engineers; a meaningful cost at fifteen plus. Corgi HomePlan offers digital certificate tools for its network members, tightly tied to the Corgi accreditation scheme.
Both produce compliant records well. The gap is breadth. If the firm also runs van checks, site inspections or risk assessments, neither covers them. Each extra workflow needs a separate system.
Option three
iAuditor: capable, generic, pricey.
iAuditor can handle CP12 records. Its template library includes gas safety forms, and for a firm already running iAuditor for other compliance checks, adding CP12 to the same platform has obvious appeal.
The limit is specificity. iAuditor was not designed for gas certificate production. Things GES does natively, automatic certificate numbering, Gas Safe registration details, landlord reminder scheduling, need manual configuration or third-party integration here.
Per-seat pricing climbs steeply. A ten-engineer gas firm on iAuditor's premium tier pays substantially more than on a dedicated gas platform. The crossover, where its breadth justifies the cost, typically sits around forty-plus staff with diverse workflow types. For a pure gas firm, it is overspecified in some places and underspecified in others.
Option four
Quickler: the CP12 happens in the chat.
Quickler runs the workflow through WhatsApp during the job, not a separate app afterwards. The engineer arrives, the workflow triggers by scheduled message or manually, and questions arrive in the chat: appliance details, operating pressure, gas rate, flue gas readings, CO alarm presence, visual inspection findings. The engineer answers by text or voice note.
Voice notes are transcribed automatically. Say "operating pressure 19 millibars, within tolerance" at the boiler and the transcript captures it in real time. No typing it twice, no holding it in your head for the van.
On completion the certificate generates from the collected data. The PDF exports from the dashboard and one click emails it to the landlord or managing agent, who can also get read-only dashboard access. £20 per active user per month with a £20 monthly minimum, plus a free tier of 20 reports a month, extra dormant users always free. An active user is someone who produced at least one report that month, so you only pay for who works and dormant users are free. Everything is unlimited on a paid account: reports, photos, messages and workflows. Setup takes under a week. Upload an existing CP12 form and Quickler builds the workflow from it. Try the demo or see pricing.
Side by side
Which one fits your firm.
- Paper forms are best for sole traders and very low volume. Around £0.50 per form, familiar, no learning curve, no searchable archive.
- Gas Engineer Software is best for dedicated gas firms of one to fifteen engineers. A monthly fee for each engineer, purpose-built for gas, searchable archive.
- iAuditor is best for large mixed-workflow teams. Priced per seat per month, generic, needs setup, searchable archive.
- Quickler is best for firms wanting one platform with low friction. £20 per active user per month, dormant users free, everything unlimited, no new app, runs in WhatsApp, searchable archive.
Questions, answered
What software do gas engineers use to produce CP12 certificates?
UK gas engineers use paper forms, Gas Engineer Software (GES), Corgi HomePlan digital tools, iAuditor, and WhatsApp-based platforms like Quickler. Paper remains common for sole traders. GES and Corgi tools are the most widely used dedicated gas certificate software. iAuditor and WhatsApp-based tools appeal to firms who want one platform across multiple workflow types.
Does CP12 software need to be approved by Gas Safe?
No. Gas Safe Register does not certify or approve software products. The legal requirement is that the record contains all required fields under the Gas Safety (Installation and Use) Regulations 1998 and that the engineer completing it is Gas Safe registered. The medium, paper, app, or WhatsApp, is irrelevant as long as the record is complete and retainable.
How quickly must a CP12 be sent to a landlord?
Under the Gas Safety (Installation and Use) Regulations 1998, a landlord must give a copy of the gas safety record to a new tenant before they occupy the property, and to existing tenants within 28 days of the check being carried out. The engineer must provide a copy to the landlord or their agent promptly after the check.
What is the difference between a CP12 and a gas safety record?
They are the same thing. CP12 is the Corgi-era trade term that persisted after Gas Safe Register replaced Corgi in 2009. The formal name under current regulations is the Gas Safety Record. Both refer to the annual landlord gas safety check certificate required under the Gas Safety (Installation and Use) Regulations 1998.
Gas safety