Whole House Generator Cost Calculator
A standby generator turns on automatically when the power goes out. The size in kilowatts and your fuel setup drive the installed cost.
Most homeowners pay $10,300 to $18,000 for an 18 to 24 kW air-cooled unit.
Your estimate
- Materials and labor
- Add-ons
- Permit and inspection
National installed prices, materials and labor included. Your local quotes may differ.
Whole house generator cost by option
Installed totals, with standard conditions and permit and inspection included.
| Option | Typical total |
|---|---|
| 10 to 14 kW air-cooled unit | $7,300 to $13,000 |
| 18 to 24 kW air-cooled unit | $10,300 to $18,000 |
| 26 kW air-cooled unit | $11,300 to $21,000 |
| Liquid-cooled unit, 30 kW and up | $21,300 to $38,000 |
What drives the price
- SizeA generator sized to run the whole house, including central AC, costs more than one sized for essential circuits.
- FuelNatural gas is convenient where available. Propane needs a tank on site.
- Transfer switchAn automatic transfer switch is required and is usually included in installed quotes.
- Site workDistance from the gas meter and electrical panel, plus local setback rules, affect the price.
How this estimate works
The calculator starts from the installed price range for the type you pick, then adds any extras you tick and typical permit and inspection. The headline number is the midpoint of your range. Low-end prices fit simple jobs in lower-cost areas. High-end prices fit complex jobs, premium brands and high-cost metros.
Get at least three written quotes before you hire. Ask each contractor to list materials, labor, permits and disposal separately so you can compare them line by line. Read how we build our ranges.
Common questions
How long do standby generators last?
Air-cooled standby generators commonly last many years with annual maintenance.
What size generator do I need?
It depends on which appliances you want to run at once. An installer can do a load calculation.
How much fuel does a generator use?
Usage depends on size and load. Check the manufacturer's fuel consumption chart for your model.
Sources and method
Price ranges are national installed estimates maintained by the HouseMath editorial team and last reviewed September 2026. For the labor side of the job, see the U.S. Bureau of Labor Statistics Occupational Employment and Wage Statistics data for electricians (SOC 47-2111), which shows how trade wages differ by state.