How to Start a Gas & Heating Business in the UK (2026)
Of all the trades, gas is the one where the rules are absolute: by law, you must be on the Gas Safe Register before you do any gas work — there is no self-certify-it-yourself route and no grey area. Work on gas without registration and you're committing a criminal offence with fines typically from £5,000 per offence, possible imprisonment, and invalidated insurance. This guide takes you from qualifications to a registered, trading business, in order.
Step 1 — Get qualified (ACS)
You can't register with Gas Safe until you can prove competence through a recognised awarding body. Two routes:
- New entrants: an NVQ/SVQ, typically via a Managed Learning Programme (MLP) — a minimum of around six months building a portfolio of real work alongside a Gas Safe registered engineer, then assessment.
- Experienced engineers: the ACS (Accredited Certification Scheme) — accelerated training plus practical and written assessments.
Your qualifications are modular — you're only licensed for the categories you hold:
- CCN1 — core domestic gas safety (the foundation everyone starts with)
- CENWAT — central heating boilers & water heaters
- CKR1 — cookers · HTR1 — fires · WAT1 — water heaters
- LPG (e.g. CONGLP1PD) and commercial (e.g. COCN1) as separate add-ons
⚠️ Every ACS qualification must be re-certified every 5 years. You also generally need to hold registration for a year before adding new appliance categories.
Build my free checklist →Step 2 — Apply to the Gas Safe Register
Once your awarding body sends your evidence of competence to Gas Safe, you apply online.
- Apply here: https://www.gassaferegister.co.uk
- Fees (confirm current figures on the register — they change): a business application is in the region of £190 + VAT, plus a per-engineer fee; annual renewal is roughly £140–£160 + VAT per engineer. (Some providers quote a combined new-engineer first-year figure of around £368 inc VAT.)
- Probation: new registrations carry a 3-month probationary period — you must notify your completed gas work and may be inspected before becoming fully registered.
- You'll receive a Gas Safe ID card showing exactly which categories you're qualified for. Customers can check it against the live register.
Gas Safe replaced the old CORGI scheme in 2009 and is run on behalf of the Health and Safety Executive (HSE).
Build my free checklist →Step 3 — Register your business with HMRC
- Sole trader — register for Self Assessment, get a UTR.
- Limited company — Companies House (~£50 online) + Corporation Tax.
Register within 3 months of starting to trade.
- Self-employed: https://www.gov.uk/set-up-self-employed
- Limited company: https://www.gov.uk/limited-company-formation
Step 4 — Register for CIS
Gas and heating engineers working for builders/main contractors are CIS subcontractors — registering drops deductions from 30% to 20%. Hiring your own subcontractors makes you a contractor too.
- Subcontractor: https://www.gov.uk/what-you-must-do-as-a-cis-subcontractor
- Contractor: https://www.gov.uk/what-you-must-do-as-a-cis-contractor
Step 5 — Insurance
- Public liability — effectively essential and required to register as a business; minimum £2m, £5m often preferred.
- Employers' liability — legally required if you employ anyone.
- Tools & van cover and professional indemnity — recommended.
Step 6 — Practical setup and growth
- Business bank account.
- VAT — register once turnover exceeds £90,000: https://www.gov.uk/vat-registration
- Waste carrier registration if you transport waste: https://www.gov.uk/waste-carrier-or-broker-registration
- Future-proofing: the heat-pump transition is a major growth area. Adding MCS certification lets you install air-source heat pumps and access the Boiler Upgrade Scheme grant (£7,500 per ASHP in 2026, paid to the installer). Many gas engineers add heat-pump and renewables tickets to stay ahead.
Gas & heating business requirements at a glance
| Requirement | Needed? |
|---|---|
| Gas Safe registration | ✅ Legally mandatory for any gas work |
| ACS qualifications (CCN1 + appliance modules) | ✅ Required to register |
| ACS re-certification every 5 years | ✅ Ongoing |
| Annual Gas Safe renewal | ✅ Every 12 months |
| HMRC registration | ✅ Sole trader or limited company |
| CIS registration | ✅ If subcontracting or hiring |
| Public liability insurance | ⚠️ Effectively essential / required to register |
| Employers' liability | ✅ Legal if you employ anyone |
| VAT registration | ✅ Once turnover > £90,000 |
| MCS certification | ⚪ Optional — unlocks heat pumps & grant work |
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Build my free checklist →Frequently asked questions
Is Gas Safe registration a legal requirement? Yes — absolutely. Under the Gas Safety (Installation and Use) Regulations 1998, anyone carrying out gas work must be on the Gas Safe Register. Unlike electrical Part P, there is no self-certification or Building Control alternative. Working on gas without it is a criminal offence.
Do I need qualifications before I can register? Yes. The Gas Safe Register is not a training body — you must already hold the relevant ACS (or NVQ/SVQ) qualifications, sent to Gas Safe directly by your awarding body, before you can apply.
How often do I renew? Gas Safe registration renews every 12 months; your ACS qualifications must be re-certified every 5 years.
When must I register for VAT? Once turnover passes £90,000 in any 12-month period.
Last reviewed: 2026. Gas Safe and ACS fees and rules change — always confirm current figures and requirements on gassaferegister.co.uk before acting.