Often yes, sometimes no. It depends less on the number on the main breaker and more on what else your home already uses. The right answer comes from a load calculation.
Can a 100 amp panel handle an EV charger?
Many 100-amp homes with gas heat, a gas range and a gas dryer can add a modest Level 2 charger. A 100-amp home with electric heat, an electric range and dryer, central air and a hot tub may not have room. Two houses with the same panel can get different answers.
What is a load calculation?
A load calculation is the method the electrical code uses to estimate your home's demand: square footage, kitchen and laundry circuits, and the nameplate ratings of fixed appliances, heating and cooling, with code-allowed demand factors. Utilities and inspectors may ask for one when you add big loads. Try our rough panel check for a first look; it is simplified and is not a substitute.
What if my panel is too small?
- Turn the charger down. Many chargers can be set to 16, 24 or 32 amps. Overnight, that is often plenty.
- Load management. Listed energy-management devices or "smart" panels and splitters can limit charging when other loads run. Current code recognizes these systems, but they must be listed and installed correctly.
- Service upgrade. If you are planning an EV plus a heat pump or solar, a 200-amp service upgrade (IES from $6,500) may be the long-term answer.
Running out of breaker spaces is a different problem from running out of capacity; a subpanel can fix spaces.
About these prices: rough starting-at prices from the IES price book. The final price depends on what we find on site, your utility and your city or county. Estimates are free.
Common questions
Can a 100 amp service support an EV charger?
Often, especially in homes with gas appliances and a charger set to 24 or 32 amps. A load calculation is the only reliable way to know.
Do I need a 200 amp panel for an EV charger?
Not always. Many homes add a charger without upgrading by choosing a lower charging rate or a load-management device. A service upgrade is needed when the load calculation shows no room.
General information for California homes under the California Electrical Code (based on the NEC). Local rules and inspectors can vary. Not a substitute for an on-site inspection. Never work inside a panel, at the meter or on live circuits.