Whole House Generator Cost 2026: Unit, Installation and Upkeep

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The third outage of the summer hits on a Sunday night. Two streets over, one house still glows: porch light on, AC humming, a low engine sound from a box beside the garage. That’s a standby generator, and a lot of homeowners start pricing one the next morning. The sticker on the box turns out to be only part of the bill.

A whole house generator costs about $8,000 to $16,000 installed, according to Generac, including the generator itself. The unit alone lists from about $3,600 to $7,500 depending on size (maker list prices, October 2026). The rest pays for installation, a transfer switch, the gas line or propane tank, a pad and permits. Then plan on yearly service and fuel.

Below: each cost from a named source, a sample budget, running costs, and how standby compares with batteries and portables.

Prices change often. The prices below are what we saw at the maker or in the named cost guide in 2026; dealers set the final price, so check current prices and get written quotes before you buy.

Whole house generator cost at a glance

Cost item	Typical range	Source (year)
Total, installed, generator included	$8,000–$16,000	Generac (seen October 2026)
Generator unit, 10–26 kW air-cooled	$3,649–$7,546 list	Generac, Kohler, Briggs & Stratton list prices (October 2026)
Installation labor	$1,500–$5,000	HomeAdvisor (June 2026)
Transfer switch, installed	$800–$2,000	HomeAdvisor (June 2026)
Concrete pad	$50–$75 per sq ft (about $1,000 for 18 sq ft)	HomeAdvisor (June 2026)
Gas line	$300–$1,000 if gas is already in the house; $2,000+ from a nearby main	HomeAdvisor (June 2026)
Propane tank	$300–$1,500	HomeAdvisor (June 2026)
Permits	$50–$200 each (usually one electrical, one fuel); another HomeAdvisor guide says $400 and up	HomeAdvisor (June 2026)
Subpanel or panel upgrade, if needed	$500–$2,000 subpanel; $750–$2,000 for a 100 A to 200 A panel	HomeAdvisor (June 2026)
Yearly maintenance	$80–$300 per year	HomeAdvisor (June 2026)

HomeAdvisor’s headline average for generator installation, $5,157 (2026), mixes in small and portable units, so for a true whole-house standby system Generac’s $8,000–$16,000 is the better starting point.

Unit price by size: maker list prices

These are the makers’ “MSRP from” prices for the generator only (October 2026); dealers set the final price. On natural gas most units make less power than the name says, so use that number if you have utility gas.

Model	kW on natural gas	kW on propane	Warranty	List price (maker, Oct 2026)
Generac Guardian 10kW (7171)	9	10	5-year limited	$3,649
Generac Guardian 14kW (7223)	14	14	5-year limited	$4,569
Generac Guardian 18kW (7226)	17	18	5-year limited	$5,379
Generac Guardian 22kW (7042)	19.5	22	5-year limited	$6,119 ($6,979 with a 200 A switch, 7043)
Generac Guardian 24kW (7209)	21	24	5-year limited	$6,559
Generac Guardian 26kW (7290)	22.5	26	5-year limited	$6,989
Kohler 20RCA	18	20	Premium 5-year limited	$6,016
Kohler 26RCA	24	26	Premium 5-year limited	$7,546
Briggs & Stratton PowerProtect 26kW	24	26	10-year comprehensive limited	$6,970
Champion 22kW aXis + 100 A switch (201219)	19.8	22	10-year limited	Not shown on maker site

Warranties differ: Briggs & Stratton calls its 10-year warranty comprehensive (parts, labor, service), Champion lists 10 years limited, Generac and Kohler five. Not sure what size you need? Our guide to what size generator you need walks through the math.

Standby generators are sold and installed through the makers’ authorized dealers, not on Amazon.

What installation pays for

Generac lists the dealer’s job in four steps: prepare the site (a concrete slab or pea gravel), connect the fuel line, install the transfer switch next to your main breaker panel, and test the system with a simulated outage. The work takes hours, but the whole process can take weeks.

Labor

HomeAdvisor puts installation labor for a permanent home generator at $1,500 to $5,000 (2026). Distance to your panel and gas meter and local rates drive the number. This work needs a licensed electrician and, for the fuel side, a licensed gas fitter or plumber. Generac says DIY installation is possible but “strongly advisable” to leave to a certified professional, and only its authorized dealers can do warranty work.

Automatic transfer switch

The automatic transfer switch disconnects your home from the grid and starts the generator when the power drops, then switches back when it returns. HomeAdvisor notes that the National Electrical Code requires one, and it is what keeps power from backfeeding onto utility lines. Some models include one: Generac’s 22kW with a 200 A whole-house switch lists at $6,979 versus $6,119 without, about $860 more. Champion’s 22kW aXis comes with a 100 A switch. HomeAdvisor puts a transfer switch at $800 to $2,000 installed (2026). Read more in our transfer switch guide.

Gas line or propane tank

Natural gas: if gas is already piped to your home, HomeAdvisor puts a new line to the generator at $300 to $1,000; running service from a nearby main costs $2,000 or more (2026). The pipe must be sized for the generator’s full load, and Generac’s spec sheet calls for 3.5 to 7 inches of water column of gas pressure at the generator, so your installer may need the gas utility to confirm the meter can feed the generator plus your furnace and water heater. More on fuel in our natural gas energy guide.

Propane: HomeAdvisor puts a propane tank at $300 to $1,500 (2026), plus the first fill. Generac says its home standby generators need a minimum 250-gallon tank, and a grill cylinder can’t run one. Many homes use a larger tank for longer outages. Some propane suppliers lease tanks instead of selling them, so ask. See propane energy for how propane compares as a fuel.

Pad and placement

HomeAdvisor puts a concrete pad at $50 to $75 per square foot, about $1,000 for an 18-square-foot pad (2026); Generac also mentions pea gravel as a base. Under the NFPA 37 standard, as Generac summarizes it, the generator must sit at least 5 feet from operable windows, doors, vents and other openings, with 3 feet clear at the front and ends and 5 feet above. Tested Generac units can sit 18 inches from the wall. Local codes come first.

Permits and inspections

Generac says all required permits must be secured before installation. HomeAdvisor’s main generator guide puts permits at $50 to $200 each, usually one electrical and one for the fuel line or tank, while its natural gas generator guide says $400 and up (both 2026). Fees are set locally, so make sure each quote lists them.

Electrical upgrades

Older or full panels can add cost. HomeAdvisor puts a subpanel for essential circuits at $500 to $2,000 and an upgrade from a 100 A to a 200 A panel at $750 to $2,000 (2026). A load manager, which sheds big loads like an AC, can let a smaller generator cover the house.

A sample budget: 22 kW on natural gas

An illustration from the ranges above, not a quote: Generac 22kW with a 200 A switch at list price, a concrete pad, gas already in the house, two permits.

Item	Low	High
Generator + 200 A transfer switch (Generac list)	$6,979	$6,979
Installation labor	$1,500	$5,000
Concrete pad	$1,000	$1,000
Gas line from existing service	$300	$1,000
Permits (two)	$100	$400
Total	≈$9,900	≈$14,400

That lands inside Generac’s $8,000–$16,000 range. Add $750 to $2,000 if the panel needs an upgrade, or $2,000+ for new gas service. On propane, swap the gas line for a tank ($300–$1,500) plus the first fill.

What it costs to run each year

Maintenance

HomeAdvisor suggests budgeting $80 to $300 a year for professional service (2026). Generac’s schedule calls for an oil and filter change after the first 25 hours of break-in, then every 200 hours or every two years, whichever comes first, with more frequent changes in very hot or cold climates. A standby generator also runs a short self-test every week; on the Generac 22kW the exercise lasts five minutes.

Fuel

In a normal year, fuel is a small cost: the weekly test adds up to about four hours of running. In a long outage it adds up. These are our estimates using Generac’s spec sheet and U.S. Energy Information Administration (EIA) average residential prices; your rate and your home’s load will differ.

Generac 22kW at half load	Fuel use (Generac spec sheet)	Price used (EIA, 2026)	≈ Per hour	≈ Per day (24 h)
Propane	2.53 gal/hour	$2.67/gal (U.S. residential average, early 2026)	$6.75	$160
Natural gas	about 200–230 cu ft/hour	$13.96–$26.45 per 1,000 cu ft (U.S. residential, January–July 2026)	$2.80–$6.10	$65–$145

At full load, the same generator uses 3.90 gallons of propane an hour. If your home draws less than half the generator’s output, real use is lower. For propane, a 250-gallon tank holding 200 gallons would last about 79 hours at half load (200 ÷ 2.53), so keep the tank topped up before storm season.

Standby generator vs home battery vs portable generator

	Standby generator	Home battery	Portable generator + transfer switch
Typical cost	$8,000–$16,000 installed (Generac)	$15,647 average for 13.5 kWh installed (EnergySage, August 2026)	$1,179–$1,399 for an 8–10.5 kW model (maker prices, Oct 2026) + $500–$2,000 for a manual switch (HomeAdvisor, 2026)
How long it runs	As long as gas flows or the propane lasts	Hours to days, depending on loads; solar can recharge it	About 8–10 hours per tank at half load; you refuel
Switchover	Automatic, in seconds	Automatic, near-instant	Manual: you wheel it out, start it, plug in
Upkeep	Yearly service, weekly self-test	Little; check the app	Oil changes, fresh or stabilized gasoline
Noise and exhaust	About 65–69 dB(A); exhaust outdoors	Silent; no exhaust	About 72–74 dB on big open-frame models (maker figures); exhaust outdoors

Home batteries cost about as much as a standby generator or more, and EnergySage’s average buys 13.5 kWh, which won’t run central AC and an electric range for days on its own. They make the most sense with solar, which refills them, or where a utility pays you to share the battery with the grid. There’s no federal tax credit for batteries installed in 2026 (the 25D credit ended for systems installed after December 31, 2025), but check DSIRE for state and utility programs. See our full breakdown of home battery backup cost and the head-to-head home battery backup vs generator.

Portable generators cost a fraction as much. A big dual- or tri-fuel model with an electrician-installed transfer switch or inlet box can run a fridge, furnace, well pump and lights. The trade-off is work and risk: you set it up in the storm, store gasoline (with stabilizer, rotated regularly), and refuel only after the engine cools.

Whatever you run, follow the U.S. Consumer Product Safety Commission’s carbon monoxide rules for portable generators: operate them outdoors only, at least 20 feet from the house, with the exhaust pointed away from windows, doors and vents, and never in a garage, basement or shed, even with the door open. CPSC also says to put working CO alarms (battery-operated or with battery backup) on every level of the home and outside sleeping areas. Built-in CO shut-offs like DuroMax’s CO Alert and Champion’s CO Shield help, but they don’t replace alarms. Never plug a generator into a wall outlet to power the house; FEMA warns against it. Backfeeding can injure utility workers and start a fire. A licensed electrician installs the transfer switch or interlock, with a permit where required, and an interlock kit must match your panel’s brand and listing. Our guide on how to run a generator safely has the full checklist.

For quiet, fume-free power for a fridge, Wi-Fi and a CPAP, a large portable power station is a third option; see the best portable power stations for home backup.

How to get a fair price

• Get 2–3 quotes from licensed installers. Ask authorized dealers for more than one brand if you can. Generac and Kohler dealers assess your home first; Generac says its in-home estimate is free.
• Compare line by line. Each quote should list the unit and model number, transfer switch (amps), pad, gas or propane work, wire run, permits, electrical upgrades, startup testing and the warranty.
• Size from a load calculation. Ask the installer which circuits the generator will cover and whether a load manager lets a smaller unit do the job.
• Check licenses and permits. The electrical and gas work should be done by licensed trades, with permits pulled and inspections passed.
• Ask about service. What does yearly maintenance cost, and who answers when it won’t start in a storm?
• Look for local help. There’s no federal tax credit for generators. Check your state, county and utility for rebates or permit-fee breaks.

See it at Generac

See it at Kohler

See it at Briggs & Stratton

Keep exploring: our home generators guide covers every type, the best generator for a house power outage compares portable picks, and home battery backup explains the battery route. Browse everything in Generators and Home Battery Backup.

Whole house generator cost questions

How much does a whole house generator cost installed?

Generac says a home standby generator costs $8,000 to $16,000 installed, including the generator. Where you land depends on the size, how far the gas line and wiring run, whether you need a propane tank or a panel upgrade, and local permit fees and labor rates. Get 2–3 written quotes from licensed installers to see your real number.

How much does a 22kW Generac generator cost?

Generac lists the Guardian 22kW (7042) from $6,119 for the unit alone, or $6,979 with a 200 A whole-house transfer switch (7043), as of October 2026. Installation, the pad, gas work and permits come on top. On natural gas it’s rated 19.5 kW; on propane, 22 kW.

Is a whole house generator worth it?

It’s worth it most where outages are long or frequent, someone depends on medical equipment, or a well pump, sump pump or heat can’t go without power. For short, rare outages, a portable generator with a transfer switch or a power station costs far less. With solar, a battery may fit better.

Is there a tax credit for a whole house generator in 2026?

No federal credit applies to a home standby generator in 2026, and the federal 25D credit for home batteries ended for systems installed after December 31, 2025. Some states, counties and utilities offer rebates or programs for backup power or batteries; search your ZIP code on DSIRE and ask your utility.

How much does it cost to run a whole house generator?

By our estimate from Generac’s spec sheet and EIA 2026 prices, a 22 kW unit at half load burns about $160 a day of propane or roughly $65 to $145 a day of natural gas. Outside outages, fuel for the weekly test is small. Add $80 to $300 a year for maintenance (HomeAdvisor, 2026).

Can I install a standby generator myself?

Generac says it’s possible but strongly advises a certified professional, and only its authorized dealers can do warranty work. The job involves house wiring, a transfer switch and gas piping, so it should be done by a licensed electrician and gas fitter, with permits and inspections where your town requires them.