Quick answer
Upgrade from 100A to 200A when load calculation exceeds safe capacity, you add EV + heat pump, have fuse box or recalled panel types, or need AFCI/GFCI modernization across the home.
- Compare practical options by risk, cost range, and comfort outcome.
- Identify what to verify in an estimate before you sign.
- Choose a path that fits your budget and timeline.
Pre-EV or pre-heat-pump
Schedule assessment before equipment delivery — avoids delay.
Compare your options
200A upgrade
Standard for modern electrified homes; includes utility coordination.
Smart panel alternative
SPAN load management may defer upgrade — see smart panel guide.
Key terms and context
This guide is written for electrical decisions in the Puget Sound. It uses the same terminology you'll hear from inspectors, technicians, and permit offices.
Overloading 100A
Tripping main breaker, overheating bus — fire and insurance risk.
How we build this guidance
- Straight answers first, so you know your options without the fluff.
- Written and reviewed by techs who do this work every day.
- Specific to Puget Sound homes, weather, and utilities.
- Updated 2026-06-08 from real electrical jobs around the region.
Methodology: Load calc per NEC 220; pricing from published cost guide ranges.
Last updated: 2026-06-08
Ready for the next step?
Get a free, no-obligation estimate from Eco — honest range before any work begins.
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Common questions
Will PSE upgrade my service?
Utility upgrades service entrance; Eco coordinates panel and load side.