Whole House Generator Cost
Whole house generator cost runs about $5,000 to $25,000 for a standby unit, according to HomeAdvisor. Generac's own estimate for a typical home standby install, generator included, is $8,000 to $16,000. Size is the biggest driver, then fuel, the transfer switch and how far the unit sits from your gas line and panel.
Price ranges at a glance
| Item | Typical cost |
|---|---|
| Standby generator | $5,000 to $25,000 |
| Portable generator | $500 to $2,000 |
| Installation labor for a permanent unit | $1,500 to $5,000 |
| Manual transfer switch | $500 to $2,000 |
| Automatic transfer switch | $2,000 to $30,000 |
| Concrete pad | $50 to $75 per sq ft, about $1,000 for an 18 sq ft pad |
| Permits | $50 to $200 each, usually two |
| Propane tank, if no gas service | $300 to $1,500 |
| Gas line from an existing gas service | $300 to $1,000 |
| Yearly professional maintenance | $80 to $300 |
Treat these as national ranges. Your quote can land outside them in a high-cost metro or on a hard site.
Unit price by size
The generator itself, before installation:
| Size | Unit cost |
|---|---|
| 7.5 to 10 kW | $2,000 to $3,500 |
| 14 to 18 kW | $4,000 to $5,500 |
| 20 to 24 kW | $5,000 to $6,500 |
| 26 to 32 kW | $6,500 to $15,000 |
| 36 to 38 kW | $14,000 to $16,000 |
| 45 to 48 kW | $16,200 to $21,000 |
HomeAdvisor's natural gas guide gives similar unit ranges, such as $4,000 to $5,800 for 10 to 20 kW. Above 30 kW, units move to liquid cooling, which adds a few thousand dollars. For a sense of brand pricing, HomeAdvisor lists starting costs of $2,000 for Champion, $3,150 for Briggs & Stratton, $3,700 for Cummins and $6,000 for Generac.
What moves the price
Size and whole-house vs essential circuits. HomeAdvisor calls capacity and fuel type the main drivers of the final installed price. A whole-house system needs a bigger generator and a service-rated transfer switch. An essential-circuit setup can drop you a size or two.
Distance. Generac says the closer the generator sits to the gas line and the electric meter, the less the install costs. Champion treats under 20 feet of gas pipe and wire as an optimal run. Every extra foot of trench and pipe shows up on the bill.
Gas supply. Hooking to an existing gas service runs $300 to $1,000, while running a line from a nearby main can cost $2,000 or more. Your utility may also need to upgrade the gas meter. Propane homes pay for the tank instead.
Electrical work. An older or full panel may need a subpanel at $500 to $2,000, or a full panel replacement. A load management module can cost less than buying a bigger generator.
Permits and local rules. HomeAdvisor's whole-house guide lists permits at $50 to $200 each, while its natural gas guide says $400 or more. That spread is why you should ask the installer to itemize permits.
Extras. A wireless monitor runs $200 to $400 and a smart load manager $150 to $300.
Running and upkeep costs
The bill doesn't stop at install. HomeAdvisor estimates about $40 to $50 a day to run a 10 kW natural gas unit, and about $90 a day for a 21 kW unit running continuously. Generac recommends service every 6 months, and professional maintenance runs $80 to $300 a year.
How to get a fair quote
- Get a load calculation, not a guess. The installer should list what the generator will carry and why that size.
- Get at least three quotes, each itemized: unit, transfer switch, pad, gas work, electrical, permits, startup and first service.
- Ask who pulls the permits and whether the inspection is included.
- Check the warranty terms and who services the unit in your area.
- Ask about the gas meter. If the utility needs to upgrade it, find out who arranges that and how long it takes.
DIY vs pro
This isn't a DIY job. It involves gas piping, a transfer switch at the service panel and code inspections. Generac recommends an authorized dealer or licensed contractor so the install meets local, state and national codes. What you can do yourself is prep: clear the site, find your panel's amp rating, and list the appliances you want covered.
If the price is out of reach, a portable generator with an interlock kit covers the essentials for a fraction of the cost. Compare both on our whole house standby generators guide.
FAQ
How much is a whole house generator for a 2,000 sq ft house?
HomeAdvisor's sizing puts a 1,500 to 3,000 sq ft home in the 14 to 18 kW range, at $4,000 to $5,500 for the unit. Add installation labor of $1,500 to $5,000, plus the transfer switch, pad and permits. Central air or electric heat can push you to a bigger unit.
How much does it cost to put a whole house generator in?
Installation alone, without the generator, runs $1,500 to $5,000 for labor and materials in HomeAdvisor's natural gas guide. That covers the pad, the electrical and gas lines and equipment. HomeAdvisor lists a standby generator at $5,000 to $25,000 but doesn't say whether that range includes installation.
How much is a sump pump battery backup?
Far less than a generator. Angi puts a sump pump battery backup system at $600 to $1,200 installed, with a national average of $900. Our sump pump backup page compares it with running the sump pump off a generator.
Is a whole house generator worth it?
It's worth it when outages are frequent or long, when you're on a well or sump pump, or when someone at home needs power for medical reasons. HomeAdvisor says a standby generator often boosts home value where outages and severe weather are common. If outages are rare, a portable with an interlock is the better value.
Sources
- HomeAdvisorHow Much Does Whole-House Generator Installation Cost? (opens in a new tab)
- GeneracBackup Generator Installation (opens in a new tab)
- HomeAdvisorHow Much Does a Natural Gas Generator Cost? (opens in a new tab)
- Champion Power EquipmentWhat a Site Survey Is and Why It Is Important When Purchasing a Home Standby Generator (opens in a new tab)
- GeneracHome Standby Generator FAQ (opens in a new tab)
- AngiHow Much Does a Sump Pump Battery Backup Cost? (opens in a new tab)