AmpereTallyWhether 100 amps is enough, worked out the way an inspector does it.

What size electrical service for a 2800 sq ft house with all-electric appliances?

2,800 ft², all electric
125 A minimum
calculated load 116 A · NEC minimum 125 A · 150 A is what usually gets installed
2,800 ft², all electric116 ACalculated load125 ANEC minimum servi…
Calculated load27,880 VA ÷ 240 V116A
NEC minimum servicethe next standard size at or above the calculated load125A
Commonly installedone size up — leaves 23% headroom for an EV charger or a heat pump later150A
General lighting2,800 ft² × 3 VA8,400VA
Small appliance + laundrytwo kitchen circuits and one laundry, 1,500 VA each4,500VA
Fixed appliancesno gas service to the house23,800VA
Before demand factor36,700VA
After demand factor100% of the first 10 kVA, 40% of the rest20,680VA
Heating or coolingthe larger of the two, not both — they do not run together7,200VA

Notes

  • **Do not add up the nameplates.** Every appliance in this house adds to 36,700 VA, but NEC 220.82 counts **100% of the first 10 kVA and 40% of everything above it** — because a house never runs the oven, the dryer, the dishwasher and the disposal at the same second. That single step is why the honest answer is 116 A and the forum answer is usually double.
  • **125 A is the code minimum; 150 A is what gets installed.** Services come in fixed sizes, so "you need 116 amps" is never an answer on its own. 125 A satisfies NEC for this load today. Most electricians fit 150 A anyway, because the marginal cost at install time is small and the cost of upgrading later — new meter base, new mast, utility coordination — is not.
  • **Heating and cooling count once, whichever is larger.** Adding both is the second most common error and it pushes plenty of ordinary houses onto a 400 A recommendation they will never need.
  • **Adding an EV charger later is the change most likely to break this.** A 48 A charger adds 11,520 VA before demand factors and is the single most common reason a service that was fine for thirty years suddenly is not.
  • Panel space is a separate constraint from service size. A 200 A panel with every slot full needs a subpanel or a tandem-breaker plan, and that has nothing to do with the calculation above. And a licensed electrician's stamped load calculation is what an inspector accepts — this page is for knowing where you stand before you call one.

2800 sq ft with all-electric appliances

Calculated load 116 A. NEC minimum service 125 A. Commonly installed: 150 A.

Do not add up the nameplates

Everything in this house totals 36,700 VA. NEC 220.82 counts 100% of the first 10 kVA and 40% of the rest, because a house never runs the oven, the dryer, the dishwasher and the disposal in the same second.

That single step is why the honest answer is 116 A and the forum answer is usually double it.

Heating and cooling count once

Whichever is larger, not both. They do not run together.

Adding both is the second most common error, and it is what pushes ordinary houses onto a 400 A recommendation they will never need.

Minimum versus what gets installed

125 A satisfies code for this load today. Most electricians fit 150 A anyway.

The marginal cost at install time is small. The cost of upgrading later — new meter base, new mast, utility coordination, a day without power — is not.

Panel space is a separate problem

A 200 A panel with every slot full needs a subpanel, and that has nothing to do with the service size. Two different constraints, often confused, and the one that actually blocks the next project is usually slots rather than amps.

A licensed electrician's stamped calculation is what an inspector accepts. This page is for knowing where you stand before you call one.

Nearby sizes