What's the cost to wire a detached laneway suite for full electrical service in Toronto?

Wiring a detached laneway suite in Toronto typically runs $8,000–$18,000 for a complete electrical installation, depending on whether you're running a new service from the street, tapping a sub-panel from the main house, or doing a full standalone service entrance — and the square footage and finish level of the suite itself.

This is one of the more complex residential electrical projects in the GTA right now, and laneway suites have their own specific challenges that push costs higher than a typical garage conversion or basement apartment.

Service Strategy: Sub-Panel vs. Separate Service

The single biggest cost decision is how the laneway suite gets its power. Most Toronto laneway suites are fed from a sub-panel connected to the main house panel via an underground feeder cable. This is the most common and cost-effective approach, typically adding $3,000–$6,000 to the project just for the underground run — trenching through a Toronto backyard, installing conduit or direct-burial TECK cable, pulling the feeder conductors, and installing a 60A or 100A sub-panel in the laneway suite. The longer the run from your main house to the back of the lot, the higher this cost. A 30-metre run through an established garden with mature tree roots and hardscaping costs considerably more than a clean 15-metre run through open lawn.

If your main house has a 100A panel, you almost certainly need a panel upgrade to 200A before adding a laneway suite sub-panel — that's another $2,500–$4,500 on top of the laneway wiring costs. A licensed electrician will do a load calculation to confirm whether your existing service can support the additional dwelling unit. Don't skip this step; an undersized service feeding two households is a chronic tripping and overheating problem.

A separate Toronto Hydro service entrance for the laneway suite is the other option — the suite gets its own meter, its own account, and its own 100A or 200A service from the street. This is cleaner for landlord-tenant billing and eliminates any dependency on the main house panel, but it's significantly more expensive ($5,000–$10,000+ just for the service entrance work) and requires Toronto Hydro coordination, a new meter base, and often a new service drop from the utility pole or underground lateral. Toronto Hydro's current infrastructure in many established Toronto neighbourhoods — Leslieville, East York, the Annex, Rosedale — is already under strain, and getting a new service connection approved and scheduled adds weeks to the project timeline.

Interior Wiring Costs

Once power reaches the laneway suite, the interior wiring scope depends on the size and complexity of the unit. A typical 500–700 sq ft laneway suite with a kitchen, bathroom, living area, and bedroom will require:

General lighting and outlet circuits (typically 4–6 circuits of 14/2 or 12/2 NMD90), a dedicated 20A kitchen circuit, a dedicated circuit for the refrigerator, a dedicated 30A circuit for an electric range or induction cooktop (10/3 NMD90), a dedicated 20A bathroom circuit, GFCI protection throughout the kitchen and bathroom, AFCI protection on bedroom circuits per the Ontario Electrical Safety Code, hardwired interconnected smoke alarms on every level and outside the sleeping area (Ontario Fire Code requirement), and a CO alarm if the suite has any gas appliances or an attached garage.

Interior wiring for a suite this size typically runs $4,000–$8,000 for labour and materials, assuming the walls are open during construction. If walls are already drywalled and you're retrofitting, add 30–50% for fishing wire through finished walls.

ESA Permits and Inspections

A laneway suite electrical installation requires an ESA permit — no exceptions. The permit covers both the underground feeder run and all interior wiring. Budget $300–$600 for permit fees depending on the number of circuits and devices. Your electrician applies for the permit before starting work, and an ESA inspector visits after completion to issue the certificate of inspection. Keep that certificate permanently — it's essential for insurance, resale, and City of Toronto laneway suite registration.

Toronto also requires laneway suites to comply with the Ontario Building Code and the City of Toronto's Laneway Suite Guidelines, which means the electrical inspection is one of several inspections your project will go through. Coordinate your electrician's timeline with your general contractor so rough-in inspections happen before drywall goes up.

Practical Cost Summary

For a realistic all-in budget: a sub-panel fed laneway suite in a Toronto home with an existing 200A service runs $8,000–$12,000 for the underground feeder, sub-panel, and complete interior wiring. If the main house needs a panel upgrade first, add $3,000–$4,500. If you're pursuing a separate Toronto Hydro service, budget $15,000–$20,000+ for the full scope.

Get at least three quotes and make sure each electrician provides a written breakdown separating the underground run, sub-panel installation, and interior wiring — this makes quotes comparable and helps you understand where the money is going.

Toronto Electrical Repair can match you with licensed electricians experienced in laneway suite projects across the GTA — it's a free service and a good way to get competitive quotes from electricians who know the City of Toronto's specific requirements. Browse local electrical professionals through the Toronto Construction Network directory at torontoconstructionnetwork.com/directory?trade=electrical.