What's the difference between upgrading my panel and rewiring my whole house?

A panel upgrade replaces your electrical panel (the breaker box) with a higher-capacity one, while a rewire replaces the actual wires running through your walls — they're two completely different projects that address different problems, though they're often done together. Understanding the distinction helps you avoid paying for work you don't need, or worse, skipping work that you do.

A panel upgrade is about capacity and safety at the distribution point. If you have a 60A or 100A panel and need more power for modern loads — an EV charger, central air conditioning, a hot tub, a home office — upgrading to a 200A panel gives you the capacity to run these devices without chronic breaker trips. The panel upgrade may also include replacing the service entrance cable from your meter to the panel and coordinating with Toronto Hydro for the service upgrade. A panel upgrade in the GTA typically costs $2,000 to $5,000 and takes one day. It doesn't touch the wires running through your walls to outlets and switches.

A whole-home rewire replaces the branch circuit wiring — the NMD90 or older cable that runs from your panel through the walls to every outlet, switch, and light fixture. This is the project you need if your home has knob-and-tube wiring, aluminum branch circuits, or old copper wiring with deteriorated cloth insulation. A rewire for a typical GTA home costs $10,000 to $30,000 depending on size and takes one to two weeks. A rewire usually includes a new panel as part of the project, since you're replacing everything anyway.

Here's how to figure out which one you need. If your home has modern copper wiring in good condition but your panel is too small — maybe you have a 100A panel and want to add an EV charger and central AC — a panel upgrade alone solves the problem. The wiring in your walls is fine; you just need more power at the source. This is common in Mississauga, Markham, and Vaughan homes built in the 1980s and 1990s.

If your home has knob-and-tube wiring — the kind found in pre-war Toronto homes — you need a rewire regardless of your panel situation. K&T wiring is ungrounded, has deteriorating insulation after 80-plus years, and can't safely handle modern electrical loads. A panel upgrade without addressing the K&T is like putting a bigger fuel tank on a car with rusted brake lines.

If your home has aluminum branch circuit wiring from the 1965-1975 era, you have a third option: aluminum wiring remediation using COPALUM or AlumiConn connectors, which costs $3,000 to $12,000 and doesn't require replacing the aluminum wire itself — just making the connections safe. This can be paired with a panel upgrade if needed.

Both projects require an ESA permit and inspection. Your electrician can assess your specific situation and recommend the right scope of work. If you're unsure whether you need a panel upgrade, a rewire, or both, get two or three quotes from licensed electricians who can inspect your existing system. Toronto Electrical Repair can connect you with electrical professionals through the Toronto Construction Network who will assess your home and provide clear recommendations.