Decision guide
100 amp vs 200 amp service
A clear homeowner comparison of service capacity, project triggers and why bigger is not automatically better.
Short answer
200A provides more total capacity than 100A. The decision is not made from service size alone: existing demand, planned equipment, panel configuration, utility scope and load-management options all matter.
Key takeaways
01100A may be adequate for some homes and projects.
02200A may be practical when several high-demand loads are planned.
03A contractor’s applicable load calculation is the decision evidence.
What changes
Increasing from 100A to 200A can require more than a larger panel. Service conductors, meter equipment, the service mast or lateral, grounding/bonding and utility coordination may all enter the scope.
When 100A may remain
A modest project, lower existing demand or suitable approved load management may allow the existing service to remain.
Plan for the home, not one appliance
A ten-year equipment plan gives the contractor better information than designing around only the next EV charger or air conditioner.
Decision table
What the evidence changes
- 100A
- Potentially adequate depending on actual demand
- 200A
- Greater total capacity; may involve utility-side work
- Decision evidence
- Applicable load calculation and site assessment
Typical project sequence
From question to documented work
- 01Inventory current loads
- 02List near- and long-term projects
- 03Compare retain / manage / upgrade paths
- 04Confirm permit and utility scope
Sequence and responsibilities vary by jurisdiction, utility and scope.
Evidence
Sources and verification
Published by the 200AmpPanel.ca Research Team, a HAUSE specialist property. Updated 2026-08-31.
Questions
Frequently asked
Is 100A enough for an EV charger?
Sometimes. Charger size, existing demand, charging controls and approved energy management all affect the answer.
What should I do next?
Use the Capacity Check to organize what you know, then have a qualified electrical contractor complete the assessment required for the property and jurisdiction.
HAUSE Capacity Check
Start with what your home needs to support.
Get a transparent electrical-capacity pre-check before deciding whether to retain, manage or upgrade the service.