Questions to ask your electrician before a panel upgrade

Updated 2026-11-03 · A checklist of questions to ask before paying for a service upgrade for an EV charger, heat pump or induction range: load calculation, conductors, breaker spaces, load management and permits.

A service upgrade can cost thousands and take weeks of utility scheduling. These questions help you understand whether you need one.

About the calculation

Which method did you use (220.83/120.83, 220.82, or 220.87 utility data), and which code edition does our AHJ enforce?
Can I see the worksheet? What nameplate values did you use?
Would 12 months of utility demand data give a lower answer?

About the hardware

Service conductors: are they sized for the service rating? (NEC 310.12 covers dwelling service and feeder conductor sizing.) A panel rating alone does not prove the wires are adequate.
Busbar and breaker spaces: is there room for a two-pole breaker, or do we need tandem breakers or a subpanel?
Is the panel a brand with known problems that should be replaced regardless?

About alternatives

Could a load-managed charger or circuit-sharing device avoid the upgrade?
Could a lower charger setting, a 120 V heat pump water heater or a smaller backup heat strip get us within rating?
If we do upgrade, should we size for future loads (heat pump, induction, battery)?

About permits

Will you pull the permit? Does it include the load calculation?
Does the utility need to approve the change?

Bring a printout of our worksheet to the conversation. It is an estimate for discussion, not a stamped design.

Common questions

Should I always get a panel upgrade for an EV?

Not always. Ask for the load calculation that shows the need. Many homes can add a charger with a lower setting or load management.

Estimate only; a licensed electrician and your local authority having jurisdiction decide; not an engineering stamp.