Pricing reviewed October 2026
Generator sizes and costs
Essentials-only backup needs about 10–14 kW ($6,000–$10,000 installed); most homes need 18–26 kW ($10,000–$15,000); large or all-electric homes 26 kW+ ($15,000–$25,000).
| Home need | Generator size | Installed cost |
|---|---|---|
| Essentials only | 10–14 kW | $6,000 – $10,000 |
| Most homes | 18–26 kW | $10,000 – $15,000 |
| Large / all-electric homes | 26+ kW | $15,000 – $25,000 |
Appliance wattages are typical editorial estimates; an electrician should do a load calculation before purchase.
Know your size? Price it with the home generator cost calculator · Compare brands: Kohler vs. Generac.
Frequently asked questions
What size generator do I need for my house?
Essentials need 10–14 kW, most homes 18–26 kW, and large or all-electric homes 26 kW or more.
Can a 22 kW generator run a whole house?
A 22 kW unit covers most homes, including central air in many cases, but all-electric homes may need more. Get a load calculation.
How much does a generator cost for a new home?
Typically $10,000–$15,000 installed for most homes; adding it during construction can simplify wiring and gas runs.
Generator figures marked as from the 2026 cost guide (whole-house generator $6,000–$25,000 installed, typically $10,000–$15,000; unit $3,000–$6,000; installation $3,000–$5,000; 10–14 kW $6k–$10k, 18–26 kW $10k–$15k, 26+ kW $15k–$25k) come from the HomeGeneratorCost 2026 guide. Add-on ranges, load wattages and city factors are editorial estimates. Get written quotes from licensed installers.