Checker (formerly Gas Checker) vs Gas Engineer Software (GES)
Checker (formerly Gas Checker) and Gas Engineer Software (GES) are both CP12 certificate apps in the GasStack directory. This page compares them using only what's in our listings: prices copied from each vendor's pricing page on the date shown, plus the features and trial details we recorded. Where we don't have a fact, we say so rather than guess.
Side by side
| Checker (formerly Gas Checker) | Gas Engineer Software (GES) | |
|---|---|---|
| Starting price | from £10.99/mo | from £18/mo |
| Price details (from the vendor page) | Lite £10.99/mo (£109.99/yr); Pro £19.99/mo (£199.99/yr); Pro+ £25.99/mo (£259.99/yr) plus £10.99/mo per sub-user. All + VAT. | Starter £19/user/mo monthly (£18 on annual); Core £25 (£23 annual); Pro £32 (£30 annual). Ex VAT. |
| Free plan | No | No |
| Free trial | 30 days, no card | Yes (length not stated on pricing page) |
| Suits | sole trader, small firm | sole trader, small firm |
| Trades | gas, heating, plumbing | gas, heating, plumbing |
| Certificates in our feature list | Yes: "Unlimited certificates on every plan (gas, oil, electrical, renewables)" | Yes: "CP12 / landlord gas safety records" |
| Price checked | 20 Oct 2026 | 20 Oct 2026 |
| Listed features |
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|
| Price source | Checker (formerly Gas Checker) pricing page | Gas Engineer Software (GES) pricing page |
Which to pick
Pick Checker (formerly Gas Checker) if…
- you want the lower starting price: Checker (formerly Gas Checker) starts with from £10.99/mo, Gas Engineer Software (GES) from £18/mo (both checked on the vendors' pricing pages). That's the cheapest plan each shows, so compare the plan you'd actually use.
- you need any of these, which are in our feature list for Checker (formerly Gas Checker): Unlimited certificates on every plan (gas, oil, electrical, renewables); Quotes, invoices, job sheets; Service reminders and CRM on Pro; Works offline; KANE analyser and Zettle integrations. (Gas Engineer Software (GES) may offer some of them too; our list isn't exhaustive.)
Pick Gas Engineer Software (GES) if…
- you need any of these, which are in our feature list for Gas Engineer Software (GES): CP12 / landlord gas safety records; Service records and tightness tests; Automated service reminders (Core and up); Quotes, invoices and scheduling; Web portal plus mobile app. (Checker (formerly Gas Checker) may offer some of them too; our list isn't exhaustive.)
Before you choose
- Check it has every form you issue (CP12, warning notice, service record, commissioning, tightness test).
- Check it works offline: plant rooms and cellars have no signal.
- Look at the per-user price if you will add engineers later.
- Check whether reminders and invoicing are on the cheapest plan or only higher tiers.
Which is cheaper, Checker (formerly Gas Checker) or Gas Engineer Software (GES)?
Checker (formerly Gas Checker) has the lower starting price: Checker (formerly Gas Checker) starts with from £10.99/mo and Gas Engineer Software (GES) from £18/mo, as shown on the vendors' pricing pages (checked 20 Oct 2026).
Does Checker (formerly Gas Checker) or Gas Engineer Software (GES) have a free plan?
Checker (formerly Gas Checker): no, per its pricing page. Gas Engineer Software (GES): no, per its pricing page.
More comparisons
- Gas Engineer Software (GES) vs Gas Certificate App
- Checker (formerly Gas Checker) alternatives
- Gas Engineer Software (GES) alternatives
- All CP12 certificate apps compared
Prices are as shown on each vendor's own pricing page on the date shown, usually excluding VAT, and can change. Always check before you buy. Spotted something wrong? Report a correction.
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