Cost to Rewire a House in Toronto

Rewiring is one of the larger electrical investments a homeowner makes, and it is also one of the hardest to price sight-unseen. The honest truth is that two houses of the same square footage can differ widely in cost depending on age, wiring type, wall access, and how much of the system needs to be touched. This guide explains what drives the number and how to think about phasing the work so it fits your budget.

Everything below is for planning. A real figure for your home requires an on-site assessment, because so much of the cost is hidden behind your walls.

What "Rewiring" Actually Means

Rewiring can mean different things, and the scope changes the price dramatically.

• Full rewire: Replacing essentially all the branch wiring in the home, often along with the panel and grounding. This is the most involved and most expensive option.
• Partial rewire: Replacing the wiring in specific areas, such as the original knob-and-tube circuits while leaving newer, code-compliant runs in place.
• Remediation: Targeted replacement or correction of unsafe sections (a common approach for insurance-driven knob-and-tube or aluminum concerns).

Knowing which one you actually need is the first step, and it is exactly what an electrician determines during an assessment. Many homeowners who fear they need a full rewire turn out to need a partial one.

The Biggest Cost Factors

Size of the Home

More square footage means more circuits, more outlets and switches, more cable, and more labour. A compact two-bedroom needs far less wire and time than a three-storey home with a finished basement. Price scales roughly with the number of devices and the total length of cable runs, not just floor area.

Age of the Home and Wiring Type

Age is where Toronto's housing stock gets interesting. The city has a large number of century homes and post-war houses, and the original wiring type drives both safety needs and cost.

• Knob-and-tube (common in pre-1950s homes): This older method has no ground wire and can be a concern for insurers. Replacing it is labour-intensive because the wiring is woven through plaster walls and joists. Insurance companies in Ontario frequently require knob-and-tube to be removed or remediated, which is a common reason homeowners rewire.
• Aluminum branch wiring (common in some 1960s-1970s homes): Aluminum is not inherently unsafe, but its connections can loosen and overheat over time. Remediation sometimes means a full rewire and sometimes means approved repairs at connections rather than replacing every run. An electrician will tell you which is appropriate.
• Older copper without grounding: May need grounding added and devices updated to meet current code.

Wall and Ceiling Access

This is the factor homeowners underestimate most. Running new cable through open, unfinished walls is fast. Fishing cable through finished plaster, insulated exterior walls, and across floors that cannot be easily opened is slow and adds patching and drywall repair afterward. The same wiring job can vary substantially in price purely based on how much wall has to be opened and restored.

A home being rewired during a gut renovation, when walls are already open, is far cheaper to wire than an occupied, finished home where every run has to be carefully fished and patched.

Panel and Service

A rewire is often paired with a panel or service upgrade, especially if the existing panel is undersized, full, or outdated. Adding modern circuits and required protection may need more capacity than an old 60A or 100A service provides. If a service upgrade is part of the job, it involves coordination with your utility, which is normal.

Code Compliance Upgrades

A rewire brings the work up to the current Ontario Electrical Safety Code. That can include GFCI protection in kitchens, bathrooms, and outdoor locations, AFCI protection where required, proper grounding, and the right number of circuits for modern loads. These are not upsells; they are the code requirements that make the work legal, safe, and insurable.

Permits and ESA Inspection

Rewiring requires an Electrical Safety Authority (ESA) permit, and the work is inspected. This is a legal requirement in Ontario, not optional paperwork. The permit and inspection process protects you: it confirms the work meets code, it matters for your home insurance, and it matters when you sell, because buyers and their lawyers may ask for proof that electrical work was done with the proper permit.

The cost of the permit and the electrician's time to file it and meet the inspector is a legitimate part of any rewire quote. Be cautious of any quote that is cheaper specifically because it skips the permit. Unpermitted electrical work can create insurance problems and require expensive correction later.

Phasing the Work to Manage Budget

You do not always have to do everything at once. A good electrician can help you phase a rewire so it fits your budget and your life, while still keeping the home safe at each stage. Common approaches:

• Tackle the highest-risk circuits first. Address the knob-and-tube or aluminum sections that insurance flags or that present the biggest safety concern, then schedule the rest later.
• Align with renovations. If you are redoing a kitchen, bathroom, or basement, rewire those areas while the walls are open. This is the single biggest way to reduce cost, because you avoid paying twice for access and patching.
• Upgrade the panel first. Sometimes the right first step is increasing capacity so future circuits have somewhere to land, then rewiring room by room.
• Group by floor or zone. Doing a full floor at a time keeps disruption contained and lets you spread the investment.

Phasing has trade-offs. Splitting the work across multiple visits means more setup and sometimes more total labour than doing it all at once, and some insurers want unsafe wiring fully addressed rather than partially. The right plan balances budget, safety, and your insurer's requirements, which is a conversation to have during the assessment.

Why an On-Site Assessment Is Essential Here

More than almost any other electrical job, rewiring resists accurate phone quotes. The cost lives inside your walls: the wiring type, the access, the panel condition, and how much can be done without opening finished surfaces. A proper assessment lets an electrician see what is actually there, confirm what code requires, and give you a real plan and a real number.

To get an honest, on-site evaluation of your home's wiring and a clear rewiring plan anywhere in the GTA, call (289) 799-3802 to speak with a licensed and insured electrician.