Best Software for Gas and Heating Engineers in the UK [2026]

The certificate is the easy bit. You do the check, fill in the readings, get a signature and send it. The evening goes on everything around it: chasing the landlord whose CP12 runs out next month, digging out last year’s appliance details, invoicing the job and ringing back the call you missed while you were under a boiler.

Most gas engineer software started at one end of that. Some apps are certificate pads that later added invoicing, and others are big job management platforms with a CP12 form bolted on. The right one for you depends on whether certificates are your whole day or one part of running a firm.

We make one of these, so read our section with that in mind. Each section, ours included, says where that product falls short. Every price below comes from each provider’s own website, checked on 27 and 29 October 2026, and excludes VAT unless the provider doesn’t say.

The quick answer

If certificates are most of what you need, Gas Engineer Software (from £18 per user a month, billed annually) has the deepest gas and oil record set, Checker (from £10.99 a month) fits a sole trader’s budget, and Gas Certificate App (£18 per user a month, billed annually) puts the diary, quotes, invoices and reminders on one plan for everyone, office staff included.

To run the whole firm from one app, Mucka (free to start, £29 a month solo, £39 per user for a team) has gas, oil and F-Gas certificates, service reminders, quotes, invoices and an AI phone receptionist, and its AI drafts whatever needs doing for you to approve.

Larger firms on commercial contracts usually end up choosing between Commusoft (no public price, built for six staff or more) and Joblogic (from £49 per user, billed annually).

What a gas engineer needs from software

A general job app can store a PDF. Gas work asks for more than that:

1. Gas records built for the job rather than a blank form. You need the Landlord Gas Safety Record (CP12) and the warning notice at the very least, plus service, breakdown, commissioning and tightness test records if you do installs, and oil or F-Gas records if your work goes that way.
2. Renewals that come back round. Landlords need a gas safety check every year and the tenant needs a copy within 28 days, so the app should book next year’s visit off the certificate and hand you the repeat work.
3. It has to work with no signal, because you fill certificates in next to meters and boilers in cellars and cupboards. If the app needs a connection, you’ll end up back on paper.
4. When you go back to an address, last year’s appliances, landlord and tenant should already be there, so you only take the readings again.
5. Quotes, invoices, scheduling and getting paid, joined up with your accounts software.

The comparison at a glance

Software	From	CP12 and gas certs	F-Gas	Service reminders	AI
Mucka	Free, then £29	Every paid plan	Yes	Every paid plan	Built in, every paid plan
Gas Engineer Software	£18 per user	20 types	No	Core and up	Pro only, beta
Commusoft	Quote only	Yes	Unstated	Yes	Add-on
Checker	£10.99	Every plan	Yes	Pro and up	None
Gas Certificate App	£18 per user	Every plan	Not named	Every plan	None
Powered Now	£23 (one user)	Middle plan up	Not named	Middle plan up	Add-ons
Tradify	£34 per user*	Pro and up	No	Plus only	Plus only
Joblogic	£49 per user*	Yes	Yes	Desktop	Through sales

Prices are per month and ex VAT; GES, Gas Certificate App, Powered Now and Joblogic are on annual billing. *VAT not stated by the provider. Mucka, GES, Checker, Commusoft and Joblogic all say their certificates or forms work with no signal; Gas Certificate App works offline for new certificates on mobile; Powered Now says its app works offline; Tradify doesn’t say.

1. Mucka: best for running the whole firm, certificates included

This one is ours. Mucka is job management for heating, plumbing and HVAC firms, built around an AI engine that watches your jobs, engineers, diary and money and drafts whatever needs doing for you to approve with one tap. Nothing goes to a customer until you say so.

The certificates cover the CP12, warning notice, boiler service and breakdown records, gas testing and purging to IGEM/UP/1B Edition 4, commissioning, catering and unvented hot water records, LPG and non-domestic gas safety records, all five OFTEC oil forms, five F-Gas records for air conditioning, heat pump records and Legionella. You start one from the job in a tap, and at an address you’ve been to before it offers the appliances and tenant on file. You can scan the boiler’s data plate and the analyser screen instead of typing, and it all works with no signal and uploads when you’re back in range. When you sign off a new boiler install, Mucka fills in the manufacturer registration and chases it before the 30 days run out.

Every certificate’s next-check date goes into your service reminders. Mucka drafts the text or email, you approve it, and a landlord who needs more than one nudge can get two follow-ups that stop as soon as the visit is booked. The gas calculators do gas rate, installation volume, ventilation, pipe sizing and heat loss, and drop the result onto the certificate.

Around that sit quotes, invoices, scheduling, Xero, QuickBooks, Sage and FreeAgent sync, WhatsApp for your engineers, and an AI phone receptionist that answers in your business name, pencils jobs in for you to approve and flags a gas smell straight away. Ask it to and it will also ring a customer about one thing, like an overdue invoice or tomorrow’s visit, and tell you what they said.

Where it falls short: there’s no Bluetooth analyser link and no boiler manual library, both of which GES and Checker have. It doesn’t do electrical certificates, and certificates aren’t on the free plan.

Price: free plan for quotes and invoices; £29 a month for a solo owner, £39 per user for a team, apprentices £19, subcontractors free. 14-day free trial of everything, no card, no contract.

2. Gas Engineer Software: best for certificate-heavy gas and oil work

Gas Engineer Software, usually called GES, has been around since 2012 and says more than 7,000 UK heating businesses use it. It’s the one to beat on certificates: 20 record types covering domestic and non-domestic gas, LPG, catering, the OFTEC oil forms, an air source heat pump service record, Legionella, minor electrical works and unvented cylinders. Readings come straight in from Kane, Anton and TPI analysers over Bluetooth, there are more than 2,300 boiler manuals in the app, and it works fully offline.

Starter (£18 a month billed annually, £19 monthly) is for a single engineer and has no invoicing or service reminders; those start on Core, from £23 per user. The AI quoting, AI invoicing and Boiler AI Assist sit on Pro (£30 per user, billed annually) and are still in beta, and so is Xero, QuickBooks and Sage sync. Its AI receptionist is listed as coming soon. There are no F-Gas or air conditioning records.

Price: £18 to £30 per user a month billed annually. 14-day trial, no card, no contract.

3. Commusoft: best for larger firms with commercial contracts

Commusoft is a big UK field service platform with real depth at the commercial end: service contracts, planned maintenance, SLA tracking, van stock and asset registers. It does digital CP12s and other gas safety records, its forms work offline, and service reminders go out automatically. Its AI:den add-on covers call summaries, email replies, job reports, data plate scanning and AI quoting.

Commusoft says it is designed for businesses with six or more staff. There’s no published price, every office user and engineer needs a licence, and the standard plans run on a 12-month contract. For a contract firm in that bracket it’s a serious option, but a smaller firm may struggle to get through the door.

Price: not published. Quote from sales, 12-month standard contract.

4. Checker: best budget certificate app for a sole trader

Checker, which used to be called Gas Checker, is a certificate app first. Every plan includes unlimited records: CP12s, service and breakdown records, OFTEC oil forms, F-Gas commissioning and leak testing, heat pump and solar thermal records, and electrical certificates. Forms work with no signal, readings come in from a Kane analyser over Bluetooth, and there’s a boiler manual library that works offline.

Lite is £10.99 a month but has no service reminders, CRM or accounts sync. Pro (£19.99 a month) adds reminders and Xero, QuickBooks and Sage, but no logins for staff. Pro+ (£25.99 a month) is the team plan, with each extra engineer at £10.99 a month. We found no AI features on its site.

Price: £10.99 to £25.99 a month plus VAT, or yearly from £109.99. Free trial, no card.

5. Gas Certificate App: best for one price with everything included

Gas Certificate App is made by Trade Apps, a UK company, and has been around since 2017. Its record list runs wide: landlord and homeowner gas safety records, service, breakdown, warning notice and commissioning records, commercial, catering and LPG records, testing and purging, domestic and commercial oil, unvented cylinders, heat pump commissioning and servicing and Powerflush, down to caravan, boat and mobile catering safety records. Readings come in from Testo, TPI and Sauermann analysers, so it’s a natural fit if there’s a Testo in your van, and boiler manuals and a gas rate calculator are in the app.

The pricing is what we like most. There is one plan, and every user gets everything on it: certificates, the job diary, quotes and invoices, service reminders by email or text that the customer can accept or decline, and the desktop version for the office. An office admin costs the same as an engineer. At £18 a month billed annually, that’s the same headline price as GES Starter, which has no invoicing or reminders.

Where it falls short: offline mode is for new certificates on a phone or tablet, switched on before you lose signal, and older certificates and the desktop need a connection. QuickBooks syncs directly but Xero is an export, text reminders use credits bought separately, and we found no F-Gas records or AI features on its site.

Price: £20 per user a month, or £216 per user a year (£18 a month), plus VAT. The same price for engineers and office staff. 14-day trial, no card.

6. Powered Now: best for firms doing gas and electrical work

Powered Now is UK-built trades software with more than 80 forms and certificates, covering gas and electrical (including EICRs), plus quotes, invoices, MTD and VAT returns. The app works offline, and customers are reminded a month before a certificate expires.

Certificates and Xero or QuickBooks sync start on the Professional plan, not the cheapest one. Its PN Receptionist answers calls as an add-on from £29 a month. If you need electrical certificates alongside gas, EICRs included, it covers both in one app. Mucka has no electrical certificates, and GES stops at minor electrical works.

Price: Business £280 a year for one user (no certificates), Professional £320 per user a year, Premium £400 per user a year, plus VAT. 14-day trial, no card.

7. Tradify: best general job manager for a growing multi-trade team

Tradify is a mature, well-built job manager with timesheets, job costing and Xero, QuickBooks and Sage sync on every plan, plus purchase orders on Plus. From the Pro plan it has UK gas forms: landlord and homeowner gas safety records, warning notices, boiler records and the OFTEC oil forms.

It’s built for every trade, so the gas side is thinner. There are no F-Gas or heat pump records, service reminders are on the top Plus plan only, and its AI tools are Plus-only too.

Price: Lite £34, Pro £37, Plus £44 per user a month. VAT not stated. 14-day trial.

8. Joblogic: best for mid-market commercial contractors

Joblogic is a field service platform for contractors running SLAs, planned maintenance and compliance across a big customer base. It covers gas safety records, warning notices and CP12s, has F-Gas refrigerant tracking and PartsArena parts data, and sends service reminders by text and email from its desktop version.

Standard is from £49 per user a month billed annually, and now has a free trial. Premium and Enterprise are quote only, and Joblogic says most customers sign for 24 or 36 months. If you already run on Joblogic, Mucka can sit on top of it through a pilot integration rather than replace it.

Price: from £49 per user a month, billed annually. VAT not stated.

Alternatives to Gas Engineer Software

Your reason for leaving GES usually decides where to go. Our Gas Engineer Software alternatives guide covers this in more depth.

If it costs too much for what you use, Checker covers much of the same certificate ground from £10.99 a month, Kane analyser link included. If you’re on Starter and want invoicing and reminders without moving up a plan, Gas Certificate App includes them at the same £18, and reads Testo and Sauermann analysers as well as TPI.

If you want the AI and the phone answered now, Mucka has its engine, voice and AI receptionist on every paid plan, where GES has a Pro-only beta and a receptionist still marked coming soon. Mucka also has F-Gas records, which GES doesn’t, and an importer built for GES that brings across your customers, properties, appliances and certificates with their original signed PDFs.

A firm growing into commercial contract work should look at Commusoft or Joblogic.

Stay on GES if your day is certificates end to end and you lean on the analyser link and the boiler manuals. Checker and Gas Certificate App come closest there, both with boiler manuals in the app: Checker links to Kane analysers, Gas Certificate App to Testo, TPI and Sauermann.

Which one should you choose?

• A sole trader doing certificates most of the day on a tight budget: Checker.
• A certificate-led firm that wants one price for every user, office included: Gas Certificate App.
• A certificate-heavy gas and oil firm: Gas Engineer Software.
• An owner-run heating, plumbing or HVAC firm that wants the whole business in one place, with the reminders and chasing done for you: Mucka.
• Gas and electrical work under one roof: Powered Now.
• A multi-trade team that lives on timesheets and purchase orders: Tradify.
• Six staff or more on commercial contracts: Commusoft or Joblogic.

Most of these have a free trial, so do a real CP12 on a real job in each one you shortlist before you move your customers over.