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Standby Generator Cost in Ontario (2026): Automatic Generators by Size, Gas or Propane, the Transfer Switch, Gas Line, Pad, Clearances, ESA and TSSA, and What It Costs to Run
Electrical & Lighting
A Standby Generator: About $13,000 for a 22 kW, and Half of That Is Not the Generator
An automatic standby generator starts itself within seconds of the power failing and shuts itself off when it comes back. You may sleep through the whole thing, which is the point. The machine is only part of the bill: the gas line, the pad, the transfer switch, the electrical tie-in and the permits make up close to half. This page prices each piece, explains the transfer switch choices, and works out the fuel for a three-day ice storm.
The numbers
$13,00022 kW automatic standby, installed
$8,500 to $13,00014 to 18 kW installed
5 ftGenerac’s clearance from operable windows, doors, vents
8 to 10 Lof propane an hour at half load, 22 kW, per Generac spec sheets
| Line | Range | Default or note |
|---|---|---|
| 14 to 18 kW standby, gas or propane, installed | $8,500 to $13,000 | |
| 20 to 26 kW standby, installed | $11,000 to $18,000 | $13,000 (22 kW) |
| Inside that: gas line 30 to 50 ft, TSSA-registered gas fitter | $1,200 to $2,200 | |
| Inside that: pad | $400 to $700 | |
| Inside that: electrical tie-in | $1,800 to $2,400 | |
| Inside that: 200 A automatic transfer switch with load management | $1,400 to $1,800 | general ATS range $1,500 to $3,000 |
| Inside that: permits and commissioning | $400 to $700 | |
| Propane tank | separate | rented or bought from the propane supplier |
Take the middle of each component, $1,700 + $550 + $2,100 + $1,600 + $550 = $6,500, and the 22 kW default of $13,000 leaves about $6,500 for the machine itself. That is our arithmetic, not a dealer’s price. HST is 13 percent on top.
Why Ontario prices are all over the map: for the same size of machine, the sources we checked were thousands apart. A Barrie electrical contractor said $11,000 to $16,000 for a 22 kW. A generator dealer’s site said $10,500 to $12,500 for the same size. A GTA company said $18,000 to $35,000, but that was for whole-home units from 20 to 48 kW. Most of the gap is how far the gas line runs from the meter or the tank, and whether the transfer switch is a basic one or a 200 A whole-house switch with load management. Budget $13,000 for a 22 kW, and get two or three quotes on the same written scope.
Size It From the Loads, Not the Brochure
A 22 kW unit is the one everybody sells, and for a big house with central air and a well it is often right. For a house heated with propane or gas that only wants the well, the sump, the furnace, the fridge and the lights, a 14 to 18 kW unit does it for less: $8,500 to $13,000 installed against $11,000 to $18,000. For a house with electric heat or a heat pump with electric backup, even 22 kW may not carry everything at once, which is what load management is for.
The number that trips people up is starting current. A 1 hp submersible well pump typically runs at 1,500 to 2,000 W and needs 4,000 to 6,000 W for a second or two to start. A central air compressor is the same story, only bigger. Check the nameplate on each motor and have the installer size for the starts, not just the running watts. The sizing calculator adds them up for you.
The Transfer Switch Is the Safety Part
A standby generator permanently connected to the house wiring must have a transfer device, and connecting one permanently needs an ESA notification. The transfer switch is what separates your house from the utility line before the generator feeds it. Without it, your generator can push power back up the line to the transformer, where it becomes several thousand volts on a wire a lineman thinks is dead.
There are two common choices. An essential-circuits switch moves a handful of chosen circuits to the generator: the well, the sump, the furnace, the fridge, some lights. A whole-house switch at the service, 200 A, moves everything, and its load management sheds big loads like the air conditioner or the dryer when the generator gets close to its limit. The whole-house switch costs more and lets you use a smaller machine than you would otherwise need.
The electrical side is done by a Licensed Electrical Contractor under an ESA notification. On our own builds and renovations in Simcoe, Muskoka and Georgian Bay, that is the licensed electrical contractor we hire, under their licence and their notification; we are a builder, not an electrical contractor. The gas or propane piping to the generator is TSSA-regulated work by a registered gas contractor. Two trades, two sets of paperwork, and the quote should name both.
Where It Sits
- On a firm, level foundation as the manufacturer specifies. TSSA’s February 2025 advisory says where the manufacturer gives no guidance it accepts a compacted crushed gravel or limestone base with a non-combustible platform at least 2 inches above grade.
- Away from openings. Generac’s published clearance is 5 ft from operable windows, doors and vents, including window wells. Other brands publish their own; local codes win.
- Close to the gas and the panel. Every extra foot of gas line and cable is money. The cheapest spot is usually near the meter and the panel, if it meets the clearances.
- Where the neighbours can live with it. Noise bylaws vary by township. The automatic self-test runs for a few minutes on a set schedule, often weekly; ask what day and time it is set for.
- Above the snow. In Simcoe County the drift off a roof can bury a generator by February. Keep it out from under the eaves.
On an ICF house the gas line and the feeder both go through a concrete wall, and that means a sleeve set in the form before the pour. We put the generator on the penetration list with everything else; the wiring an ICF house page has that list. The ICFhome.ca houses are built this way.
What It Costs to Run
Generac’s published spec sheets for its 22 kW air-cooled unit show, at half load, about 2.2 to 2.6 US gallons of propane an hour, which is 8 to 10 L, or about 184 to 216 cubic feet of natural gas, which is 5 to 6 m3. The figures differ between versions of the sheet, so check the spec sheet for the exact model you are quoted. Multiply by what your last propane or gas bill says you pay per litre or per cubic metre, all in.
A three-day ice storm, 72 hours at half load, is about 590 to 700 L of propane, or about 375 to 440 m3 of gas. A propane tank has to be filled well below its size for safety. Tell the propane supplier how many hours you want to ride through and let them size the tank. A generator with an empty tank is a lawn ornament.
Then there is maintenance: oil, filters, plugs and a battery that starts it. Ask for the yearly service price in writing with the quote; we did not find a published Ontario price we would stand behind, so we do not print one.
Questions people ask
How much does a whole-house generator cost in Ontario?
A 20 to 26 kW automatic standby generator is $11,000 to $18,000 installed before HST, about $13,000 for a typical 22 kW. A 14 to 18 kW unit is $8,500 to $13,000. A propane tank is separate.
Do I need a permit for a standby generator?
Yes. Connecting a generator permanently needs an ESA notification, and the gas or propane piping is TSSA-regulated work by a registered gas contractor. Your township may have its own rules on placement and noise.
What size generator do I need for a rural house with a well?
Add the running watts of what you need, then add the biggest starting surge, which is usually the well pump: a 1 hp pump typically needs 4,000 to 6,000 W to start. Many rural houses on gas or propane heat are well served by 14 to 22 kW. The rural outage page lists the loads.
Is a generator better than a battery?
For a long winter outage in the country, usually yes. For short outages and quiet, a battery wins. The generator vs battery page weighs them.
Size the generator before you price it
The generator and battery sizing calculator takes the loads that matter in your house, the well pump, the sump, the furnace, the fridge, adds the starting surge, and gives the generator size and the installed cost. If you already have quotes, the $99 review reads up to three of them and tells you which one left out the gas line, the pad or the transfer switch.
Sources and further reading
- ESA: generator safety: transfer devices, the notification for a permanent connection, and never running a generator indoors.
- TSSA: foundations for small standby generators: the gas-side rules for setting a standby generator.
- ESA notifications and inspections: when a notification of work is needed, who files it, and the rule that nothing is covered until an inspector authorizes it.
