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Electrical Panels and Service in Ontario (2026): Panel Upgrades, 100, 200 and 400 Amp Service, Subpanels, the Utility, and Room for a Heat Pump and an EV
Electrical & LightingPanels and service
Panels and Service: A Full Panel Is Not a Full Service
Panel swaps, 100 to 200 A and 400 A, subpanels, the utility and electrification. Ontario, October 2026.
A panel is a parking lot and the service is the road out front. A lot with no empty stalls can still have a quiet road, and that is the most expensive misunderstanding in this trade: the fix for a full panel is often a $1,500 subpanel, and the fix for a full service is a $3,800 upgrade and a day with the power off. Do the load calculation first, then decide which problem you actually have.
The numbers
$2,200panel swap, same size ($1,500 to $3,000)
$3,800100 A to 200 A, overhead ($2,500 to $5,000)
$5,000+underground upgrade with a trench ($5,000 to $7,000 and up)
$92ESA contractor fee for a service change (the minimum)
Do the arithmetic before anyone quotes a panel
The code sets the size of a house service with a calculation, Rule 8-200, not with a feeling. In plain words: 5,000 W for the first 90 m2 of living area and 1,000 W for each 90 m2 or part of it after that, then the electric heat, the air conditioning or heat pump, 6,000 W for a range, any tankless water heater or hot tub heater at full value, the EV charger at full value unless a load manager limits it, and 25 percent of the other loads over 1,500 W when there is a range. Divide by 240 V for amps.
ESA's own worked example is a 140 m2 house with AC, a 12 kW range, a 32 A Level 2 charger, a dryer and a storage water heater. It came to 26,055 W, or 108.6 A, which needs at least a 125 A service. Change the charger to one capped by an energy management system under Rule 8-106 and the answer moves. That is why the service capacity calculator exists, and why electrification load planning is worth reading before you buy the heat pump. Only an LEC and ESA make the final call.
A tight house helps. An all-electric ICF house with a heat pump, induction and an EV usually fits on 200 A; the same plan in leaky frame with baseboard heat often does not. If the heat pump or electric heat size is the unknown, OntarioHeatLoss.ca does the heat loss that sets it.
The utility is part of the job
A service upgrade means the utility disconnects you, the LEC changes the service, ESA inspects, and the utility reconnects once it has ESA's connection authorization, not a minute before. Toronto Hydro charges $120 to disconnect and reconnect at the meter in regular hours. Alectra charges $65 at the meter and gives residential customers one free planned disconnect every 12 months. Hydro One does one disconnect and reconnect a calendar year for an upgrade at no charge with 10 days notice, and on Hydro One the meter base belongs to you.
How the utility handles an upgrade covers each one, the overhead and underground cases and the long rural run. For a brand-new house, hydro connection cost for a new build is the page.
The guides
Electrical panel upgrade cost
Panel swap against service upgrade, 100 to 200 A overhead and underground, 400 A, meter base and mast, the utility, the ESA fee and the day without power.
Subpanel or service upgrade?
A subpanel adds spaces, not capacity: when one is right for a garage, basement or addition, when only an upgrade fixes it, and tandem breakers.
How the utility handles a service upgrade
Hydro One, Alectra, Toronto Hydro, Elexicon, EPCOR and the small utilities: who owns what, disconnects, connection authorization and how long it takes.
Electrification load planning
Heat pump, electric backup, induction, heat pump water heater, EV and hot tub: will it fit on 100 or 200 A, and what a load manager changes.
100 or 200 amp service?
Already on the site: the long version of the question every house with an old panel ends up asking.
Hydro connection cost for a new build
Already on the site: the utility connection, poles, trenching and the long rural run.
Load and wire size calculator
Already on the site: amps, distance and voltage drop for a single circuit or feeder.
Heat pump cost in Ontario
Already on the site: what the heat pump itself costs, including the electrical work that comes with it.
Detached garage cost
Already on the site: the building, the slab and the feed from the house that the subpanel hangs on.
What it costs, October 2026
| Item | Ontario range, installed | Notes |
|---|---|---|
| Panel replacement, same amperage | $1,500 to $3,000 | $2,200 is the default |
| 100 A to 200 A upgrade, overhead | $2,500 to $5,000 | $3,800 is the default |
| 100 A to 200 A upgrade, underground with a trench | $5,000 to $7,000 and up | low published figures assume an existing conduit |
| Meter base and mast replacement | $500 to $1,500 | usually inside the upgrade price |
| 400 A service | $4,500 to $10,000 and up | plus whatever the utility charges for the transformer and line |
| Subpanel, attached garage or basement | $600 to $2,500 | $1,500 default |
| Subpanel, detached garage or shop with a trench | $2,500 to $4,500 and up | $3,500 default |
| ESA fee, service change, single dwelling | $92 contractor, $212 homeowner | contractor fee $86, the $92 minimum applies |
| Utility disconnect and reconnect at the meter | $0 to $120 | Hydro One once a year free, Alectra $65, Toronto Hydro $120 |
| Electrician hourly rate | $80 to $160 an hour | plus a $75 to $200 service call |
Worked example, overhead 100 A to 200 A upgrade in Alectra territory: the $3,800 default includes the panel, meter base and mast and the contractor's ESA filing; the ESA fee itself is $92 and Alectra gives one free planned disconnect every 12 months. A quote that adds $500 for “the utility” should say what Alectra is actually charging; ask Alectra, because if its own equipment can carry the upgrade there may be no Alectra charge at all.
Why Ontario prices are all over the map: the contractors and published price guides we checked for this page quoted very different prices for the same upgrade. A Toronto contractor advertised “overhead from $2,600”, a Toronto EV installer quoted $2,500 to $5,000 overhead and $5,000 to $7,000 and up underground, and a national home-services marketplace said $3,000 to $5,000. One GTA company printed $3,500 to $4,500 on one page and $1,400 to $1,800 on another. Overhead or underground, the meter base and mast, the trench and who pays the utility are most of it. Budget $3,800 overhead and get two or three quotes on the same written scope.
Rules of thumb worth keeping
- Load calculation first. If the service passes, you may need a subpanel or a load manager, not an upgrade. Subpanel or upgrade.
- Ask your utility what it charges. Not the contractor. Some charge nothing once a year.
- If you upgrade, go to 200 A and plan the spaces. Ask for spare spaces in the new panel; empty slots now save tandem breakers later.
- Underground in a rural yard: locate everything first. Well line, septic, the gas line; a backhoe finds them the expensive way.
- Keep the ESA certificate with the house papers. The insurer and the next buyer will ask.
Have quotes in hand? Let a builder read them first
For $99 I read up to three electrical quotes, or one quote plus photos of your panel, and put them on one grid: the service and panel, the circuit count, the devices, who supplies the fixtures, the pot light count, the exterior work, EV and low voltage, the ESA notification, the utility, patching and the warranty. You get a written answer on what each one left out, in dollars, and which one I would sign.
There is no contractor network behind it and no referral fee on who you hire. We are a builder, not an electrical contractor: on our own builds and renovations in Simcoe, Muskoka and Georgian Bay the electrical is done by the licensed electrical contractors we hire, under their licence and their ESA notification. Outside that area I will tell you honestly whether I know anyone.
Questions people ask
How much does a 200 amp upgrade cost in Ontario?
About $2,500 to $5,000 overhead, so budget $3,800, and $5,000 to $7,000 and up underground when a trench is needed. A 400 A service runs $4,500 to $10,000 and up plus the utility. Panel upgrade cost.
Will a heat pump, induction range and EV fit on 100 amps?
Sometimes. It depends on the size of the house, the heat pump and any backup heat, and whether the charger runs through an energy management system. The service capacity calculator runs the Rule 8-200 arithmetic; an LEC confirms it.
Will a subpanel give me more power?
No. A subpanel is a power bar, not a bigger wire from the street. It adds breaker spaces and shortens runs to a garage or addition; the service is still the same size.
How long is the power off for a service upgrade?
Often most of one working day for a straightforward overhead change, and it can be longer underground or if the utility has to change its own equipment; ask the contractor for the plan in writing. Plan the fridge, the sump pump and, on a well, the water.
Do I need a permit for a panel change?
Yes. Almost all electrical work needs an ESA notification filed before the work starts. The ESA fee for a service change on a house is $92 when a contractor files and $212 when a homeowner does.
Find out if you need an upgrade at all
The service capacity calculator takes your living area, heat, cooling, range, water heater, dryer, EV and hot tub and gives the calculated amps against 100, 125 and 200 A, with and without a load manager. If an electrician has already quoted an upgrade, send it to the $99 review.
Sources and further reading
- ESA Bulletin 8-3-15: demand factors: ESA’s worked load calculation for a house with air conditioning, a range and a Level 2 charger.
- Hydro One: service upgrade: how to request a service upgrade from Hydro One and what happens after the ESA notification is in.
- ESA 2026 Fee Guide: the actual ESA fees for a new house, a service change, an EV charger and renovation work, contractor and homeowner rates.
