Ontario's climate spans humid continental (Dfb/Dfa in the south) through subarctic (Dfc) along the northern Shield, making it one of Canada's strongest markets for closed-loop geothermal. The province has 37 verified geothermal contractors in our directory, concentrated in the Greater Toronto Area, Ottawa, Kitchener-Waterloo, and London. Ontario is also the only Canadian province with a dedicated provincial rebate for ground source heat pumps — the Home Renovation Savings Program covers up to $12,000 for non-gas-heated homes, with federal OHPA funding available on top for oil-heated properties.
- 37 verified contractors
- 28 cities covered
- ★ 0 avg rating
- 6 WaterFurnace dealers
- 10 IGSHPA-certified
Top Ontario cities for geothermal contractors
Ontario's verified contractors are spread across the province, with the densest coverage in the Greater Toronto Area and the Ottawa Valley. Smaller markets like Kingston, Barrie, and Sudbury have active installer bases serving rural and cottage-country properties where natural gas is unavailable and propane-to-geothermal conversions are common.
Featured Ontario geothermal contractors
Contractors are listed in order of verified review count. All 37 Ontario entries have been individually reviewed for scope: these companies install ground source heat pump systems, not air-source-only HVAC or well-drilling subcontractors.
Ontario geothermal incentives in 2026
Ontario homeowners can currently access two streams of support: a provincial rebate and a federal grant for oil-heated homes. The programs do not require a home energy audit to qualify, though your installer will need to be pre-registered in the program before you sign a quote.
- Home Renovation Savings Program — Ontario's active provincial rebate for ground source heat pumps. Enbridge Gas customers receive a flat $3,000 rebate. Homeowners on electricity, oil, propane, or wood heat receive up to $12,000 (calculated at $2,000 per ton of closed-loop capacity). Your GSHP must appear on the Energy Star Geothermal Heat Pump List or the NRCan qualified products list. Contractors must be registered in the program — the contractor registration window closes May 31, 2026, but homeowners working with an already-registered installer can still apply. The program is active and has no published end date. See homerenovationsavings.ca for the current list of registered contractors and the application portal.
- Oil to Heat Pump Affordability Program (OHPA) — Federal program for homeowners currently heating with oil, income at or below the provincial median. Geothermal (ground source) heat pumps are explicitly eligible under the program, provided the system meets the CSA C448 standard. Ontario participates in the co-delivered stream: up to $15,000 combined ($10,000 federal + $5,000 Ontario match) for qualifying households. Eligible costs include the outdoor piping loops for the ground source system. Apply through our Canadian incentives guide or directly through Natural Resources Canada.
For the full Ontario incentive matrix and eligibility details, see Geothermal Rebates in Canada.
Ontario geothermal regulations & well-drilling rules
Ontario has the most detailed regulatory framework for geothermal in Canada, governed by two separate statutes depending on the system type.
Vertical closed-loop systems (deeper than 5 metres) are governed by O. Reg. 98/12 (Ground Source Heat Pumps), made under the Environmental Protection Act. Any person who constructs, alters, replaces, or extends such a system must obtain an Environmental Compliance Approval (ECA) from the Ministry of the Environment, Conservation and Parks (MECP) before construction begins. The ECA application includes a Work Plan prepared by a licensed Professional Engineer (P.Eng.) or Professional Geoscientist (P.Geo.) covering hazardous gas monitoring, a drilling plan, a geological assessment, and a health and safety plan. The Environmental Bill of Rights (EBR) public review period adds a minimum 45 days to the timeline. The ECA application fee is approximately $1,400 — confirm the current figure with MECP before budgeting. All systems must conform to CAN/CSA-C448.1-02 (commercial/institutional) or CAN/CSA-C448.2-02 (residential). Methanol is prohibited as a heat transfer fluid.
Horizontal closed-loop systems shallower than 5 metres and direct exchange (DX) systems shallower than 5 metres are exempt from the ECA requirement, though a building permit from the local municipality is still required for any earth energy system.
Open-loop systems (aquifer heat pumps) must comply with O. Reg. 903 (Wells) under the Ontario Water Resources Act, including well construction, tagging, and record-keeping requirements. A Permit to Take Water is required if daily withdrawal exceeds 50,000 litres. A discharge approval may be required for return-water disposal.
Driller licensing. Well construction in Ontario requires a valid Well Technician Licence (Class 1 — rotary, cable-tool, or air percussion drilling) and a Well Contractor Licence (business) issued by MECP under O. Reg. 903. Whether vertical closed-loop boreholes with no water extraction meet the regulatory definition of a "well" and therefore require these licences is a question MECP has not resolved in published guidance — your installer should confirm with the MECP Wells Help Desk at 1-888-396-WELL before drilling. Heat pump loop connections require an Ontario College of Trades plumber or steamfitter; refrigerant handling on DX systems requires a refrigeration mechanic.
Setback distances for geothermal boreholes fall under O. Reg. 903, but the numeric values in that regulation could not be confirmed from publicly accessible sources. Ask your installer to confirm applicable setbacks with MECP or a P.Geo. before siting the system. Conservation Authorities may also require a permit for work near watercourses or wetlands.
For permit guidance and a checklist of required approvals, see our geothermal permits tool.
Ontario climate and ground conditions
Southern Ontario (Toronto, Hamilton, London, Windsor) sits in a humid continental climate (Dfb/Dfa) with hot summers and cold winters — average January lows of -10 to -14°C and ground temperatures around 8–10°C at depth. Closed-loop vertical systems in this region benefit from moderate groundwater tables and a mix of sedimentary bedrock and glacial overburden. The GTA has dense contractor coverage and installer experience with both residential and commercial-scale vertical loops.
Eastern Ontario (Ottawa, Kingston, Belleville) runs colder (Dfb), with average January lows near -14°C and longer heating seasons. The Shield fringe means more granite and hard-rock drilling in some areas, which increases borehole cost but delivers stable, high-conductivity formation contact. Ottawa-area contractors regularly work in both sedimentary (south) and Canadian Shield (north) geology.
Central and Northern Ontario (Barrie, Sudbury, Sault Ste. Marie, Thunder Bay) transitions to continental subarctic (Dfc). Heating degree days are substantially higher, which increases the payback advantage of geothermal over propane or electric resistance. Rural properties without gas service are the most common conversion candidates in this region. A number of contractors in the directory serve cottage country across the Muskoka and Haliburton Highlands.
Cottage-country properties and rural homes on well water are well-suited to horizontal closed-loop if lot size permits, avoiding the ECA requirement for systems shallower than 5 metres. On smaller suburban lots, vertical borehole systems are the norm.