Should my NB panel main breaker be a 200A or 400A service?

For most New Brunswick homes, a 200A service is sufficient — but larger homes with high electrical loads may benefit from 400A service.

The right service size depends on your home's size, heating system, and planned electrical loads. Here's how to think through it.

When 200A Service Is Enough

A 200A panel is the standard for most NB residential homes and has been the minimum for new construction for decades. It comfortably handles a typical home with electric heat, an electric range, a dryer, EV charging, and general lighting and outlets. If your home is under 3,000 square feet with conventional electric baseboard heating, a 200A service will almost certainly meet your needs. The vast majority of panel upgrades we see in New Brunswick are homeowners moving from an older 100A service up to 200A — and that upgrade alone solves most capacity problems.

When 400A Service Makes Sense

A 400A service becomes worth considering when you're stacking multiple high-draw systems in a larger home. Think electric vehicle charging (especially two EVs), a large electric heating system, a hot tub, a workshop with heavy equipment, and a whole-home generator — all under one roof. Larger homes over 3,500–4,000 square feet with all-electric systems can genuinely push the limits of 200A. Some homeowners also choose 400A for future-proofing, particularly as EV adoption grows and heat pumps become more common across New Brunswick.

The Practical and Cost Consideration

The cost difference is significant. A 200A panel upgrade in New Brunswick typically runs $2,000–$3,500, while a 400A service installation can run $4,500–$8,000+ depending on your location and whether NB Power needs to upgrade the service entrance from the street. That NB Power side of the work — from the transformer to your meter — is their responsibility and involves a separate coordination process. Your licensed electrician handles everything from the meter inward and will coordinate with NB Power on the service entrance upgrade.

TSANB Requirements

Any panel upgrade or new service installation requires a TSANB permit before work begins. Your electrician pulls the permit, completes the work to Canadian Electrical Code standards, and a TSANB inspector signs off with a Certificate of Compliance. This isn't optional — unpermitted panel work creates serious insurance and resale problems down the road.

The honest answer is that most NB homeowners don't need 400A, but if you're unsure, a licensed electrician can do a load calculation on your home before you commit to either option. That calculation takes into account your actual usage, planned additions, and heating system to give you a definitive answer rather than a guess.

New Brunswick Electrical can match you with a local licensed electrician who can assess your home and provide a free estimate — reach out anytime.