Going out on your own
How to start a gas fitting business in Ontario
Gas work in Ontario is regulated by the TSSA, not Skilled Trades Ontario. You need a gas technician/fitter certificate (G3, G2, or G1) scaled to the size of appliance you work on, plus a registered contractor.
Fuel Systems & Gas Fitting at a glance
- Licence to do the work
- Required — TSSA gas technician certificate (G3 → G2 → G1)
- Path in
- College gas technician program + TSSA exams — months, not years, to G3
- Regulated by
- TSSA
- Insurance baseline
- Strong CGL — confirm gas work is not excluded
Fuel Systems & Gas Fitting is a compulsory trade in Ontario. You cannot legally do this work, or hire people to, without the required certification. This is the key difference from non-compulsory trades and the first thing to sort out.
The steps to start your gas fitting business
- 1
Incorporate your company
Most contractors incorporate (Ontario or federal) to limit personal liability, look credible to larger clients, and access tax advantages once profitable. You choose a named or numbered company, set directors and share structure, and file the articles. Budget roughly $400–$600.
Full guide: Incorporation - 2
Register your CRA accounts
Get a Business Number, then register for HST/GST (mandatory once you exceed $30,000 in revenue, and worth registering sooner to claim input tax credits), a payroll account if you will hire, and corporate income tax. This is free and done through the CRA.
Full guide: CRA Registration - 3
Register for WSIB
Construction is a mandatory WSIB sector. Independent operators and partners in construction generally must register even with no employees, and clients and general contractors will require a valid WSIB clearance certificate before letting you on site.
Full guide: WSIB & Provincial - 4
Get certified and licensed for fuel systems & gas fitting
Fuel and gas work is governed by the TSSA under the Technical Standards and Safety Act. Gas fitters hold a G3 (limited residential), G2 (residential and light commercial), or G1 (unlimited) certificate. Businesses must operate as a registered gas contractor with TSSA, and oil, propane, and other fuels have their own certifications.
Full guide: Trade Licensing - 5
Get insured
Carry Commercial General Liability (typically $2M, $5M for commercial/industrial work), plus tools and equipment, commercial auto, and — depending on scope — builders risk and professional liability. Many contracts and clients specify minimum coverage before you can quote.
Full guide: Insurance - 6
Set up health, safety & compliance
Meet your Occupational Health and Safety Act duties: a health and safety policy, required training (WHMIS, Working at Heights where applicable), and — for commercial and public work — often COR® certification. This is also where any trade-specific safety tickets live.
Full guide: Safety Compliance - 7
Stand up your operations
Open business banking, set up construction-specific accounting, and understand your trust obligations under the Construction Act (holdback, prompt payment, and adjudication). This is the back office that keeps you paid and out of trouble.
Full guide: Operational Setup - 8
Get bid-ready and win work
Assemble your prequalification package — incorporation and WSIB documents, insurance and bonding letters, safety program, key personnel, and project references — then quote, send proposals, and collect on invoices. This is where a construction business actually makes money.
Full guide: Bid Readiness
Insurance for a gas fitting business
Gas carries fire, explosion, and carbon-monoxide exposure — among the highest-consequence residential trades. Carry strong CGL limits and confirm gas work is not excluded from your policy.
Your launch checklist
The whole page in one list. Screenshot it, stick it on the dash of the truck.
- Incorporate your company
- Register your CRA accounts
- Register for WSIB
- Get certified and licensed for fuel systems & gas fitting
- Get insured
- Set up health, safety & compliance
- Stand up your operations
- Get bid-ready and win work
Fuel Systems & Gas Fitting questions, answered
Do you need a licence? How much does it cost? See the FAQs.
Fuel Systems & Gas Fitting overview
Licensing, regulators, and certifications at a glance.
Skip the paperwork. Let AEC Stack set it up
AEC Stack runs the whole process for a gas fitting business: incorporation, CRA, WSIB, trade licensing, insurance, compliance, and the operations to win your first contract.
Start your fuel systems & gas fitting business