How Much Does a Whole House Generator Cost? About $6,000 to $20,000 Installed
By Sharrk Team · November 2, 2026
A whole-house (standby) generator usually costs about $6,000 to $20,000 installed. HomeGuide puts a typical job at $6,000 to $11,000 including labor, and Fixr puts it at $10,000 to $20,000 with a $15,000 average. Large units over 20 kW, or a long run from the house, can push the total to $24,000 or more.
Cost guides disagree because some quote the generator alone and others include the transfer switch, gas line and labor. Here's what each piece costs.
How much does a whole house generator cost installed?
| Source | Installed range | Notes |
|---|---|---|
| HomeGuide | $6,000 to $11,000 | Unit $3,000 to $6,000 plus labor $3,000 to $5,000 |
| HomeGuide (over 20 kW or long runs) | $9,500 to $24,000 | Bigger units and longer wire and gas runs |
| Fixr | $10,000 to $20,000 (average $15,000) | Includes all parts and labor |
| HomeAdvisor | $5,000 to $25,000 | Standby with installation, from the page intro |
HomeAdvisor and Angi (one company) also list an average generator install cost of $5,174, with a normal range of about $1,537 to $8,820. That figure spans every size, starting with small portable units (1 to 6 kW), so it runs lower than a typical standby job. Use the standby ranges above when budgeting for a whole-house unit.
How much does a generator cost by size (kW)?
Size drives the equipment price. These are prices for the generator alone, before installation:
| Size | HomeGuide unit price | HomeAdvisor unit price | Typical home |
|---|---|---|---|
| 13 to 16 kW (HomeGuide) / 14 to 18 kW (HomeAdvisor) | $3,000 to $4,500 | $4,000 to $5,500 | Under 1,500 sq ft (HomeGuide); critical circuits in 1,500 to 3,000 sq ft (HomeAdvisor) |
| 17 to 20 kW / 20 to 24 kW | $4,000 to $6,000 | $5,000 to $6,500 | 1,500 to 3,000 sq ft (HomeGuide); 3,000 to 5,000 sq ft (HomeAdvisor) |
| 22 to 25 kW / 26 to 32 kW | $4,500 to $12,000 | $6,500 to $15,000 | 3,000 to 5,000 sq ft, or extra appliances |
| 30 to 48 kW / 36 to 48 kW | $10,000 to $16,000 | $14,000 to $21,000 | Large homes or commercial-grade loads |
The two guides use slightly different size bands, so the rows line up only roughly. This Old House notes that a 20 kW standby generator should cover most home devices, and it suggests sizing for 10 to 20 percent more power than you expect to need.
What does installation include?
Installation is often as much as the generator itself. A typical job has these parts:
| Item | HomeGuide | Fixr | HomeAdvisor |
|---|---|---|---|
| Automatic transfer switch | $600 to $2,500 | $2,700 to $3,700 installed | $600 to $2,500 |
| Gas line | $12 to $25 per linear foot | $1,000 to $1,500 piping labor | No separate price |
| Concrete pad | $150 to $400 | $500 to $1,000 labor | About $1,000 for an 18 sq ft pad |
| Permits | $80 to $450 total | Varies by town | $50 to $200 each |
| Electrical labor | $3,000 to $5,000 | About $5,000 | $1,500 to $5,000 |
Other costs that can show up on a quote:
- Propane tank if there's no natural gas: $400 to $1,800 (HomeGuide).
- Electrical subpanel if needed: $500 to $2,000 (HomeAdvisor).
- Wiring to the house: $6 to $8 per foot (HomeGuide), or $1,000 to $2,000 in labor (Fixr).
- Annual maintenance: $200 to $650 a year for a service contract (HomeGuide); HomeAdvisor lists $170 to $400 and Fixr $200 to $500.
The transfer switch moves your home's circuits from the grid to the generator and back. If the panel itself needs work, see our guide to electrical panel upgrade cost.
Portable vs standby generator: which costs less?
A portable generator costs far less up front, but it does a different job.
| Portable | Standby (whole-house) | |
|---|---|---|
| Equipment | $500 to $2,500 (HomeGuide) | $3,000 to $6,000 for most homes (HomeGuide) |
| Hookup | Transfer switch $400 to $1,300, or interlock $400 to $850 (HomeGuide) | Automatic transfer switch, gas line, pad, permit |
| Starts | By hand; you plug things in | Automatically when the power goes out |
| Fuel | Refuel as it runs | Natural gas or propane from the home's lines |
Generac describes the main difference this way: a standby unit senses an outage and restores power on its own, while a portable unit has to be started, fueled and connected by the owner. This Old House prices portables from a couple hundred dollars to over $2,500 for higher-end models.
Is a portable generator safe to run during an outage?
Only outdoors and far from the house. The Consumer Product Safety Commission (CPSC) says about 100 people in the U.S. die each year from carbon monoxide poisoning from portable generators. Its guidance:
- Never run a portable generator inside a home, garage, basement, crawlspace or shed. Opening doors or windows doesn't make it safe.
- Run it outside only, at least 20 feet from the house, and point the exhaust away from buildings.
The CDC says to keep generators at least 20 feet from any window, door or vent, and to use a battery-powered or battery-backup CO detector at home. A standby unit is installed outdoors on a pad by a professional, which removes the risk of someone running it in a garage.
Why do generator calls spike during storms?
Generator demand is uneven: an outage or storm forecast can bring many calls at once. Some callers want a quote for a standby unit. Others have a portable running and want a transfer switch or interlock right away. A few have an emergency, such as a generator wired wrong or a downed service line.
Calls that go to voicemail during the rush are quotes you may never get back. For true emergencies, use a separate electrical emergency call script.
What should electricians ask on a generator call?
Use a short intake script so every caller gets the same questions and your estimator has what they need:
- "Are you calling about a new standby generator, a transfer switch for a portable, or service on an existing generator?"
- "Is anything unsafe right now, like burning smells, sparking, or a generator running inside the house or garage?" If yes, transfer the call to your on-call tech right away, and tell the caller to call 911 if anyone feels sick.
- "Do you have natural gas service, or would this run on propane?"
- "Roughly how big is the home, and what must stay on during an outage: whole house, or just the furnace, fridge, well pump and medical equipment?"
- "How far is the electrical panel from where the generator would sit outside?"
- "Do you own the home? Is there an HOA we should know about?"
- "What's the best time for an on-site estimate, and the best number and email for the quote?"
Questions 3 to 5 cover the biggest price swings: fuel, size, and run length.
How does Sharrk handle generator calls?
Sharrk answers calls 24/7, asks your generator intake questions, and books the estimate onto Sharrk's calendar, Calendly or Cal.com, or into ServiceTitan. It can live-transfer a caller to a person when a call needs your team, such as a safety problem. New leads from Angi, Thumbtack, Networx, web forms and webhooks get a reply in under 30 seconds, and Jobber clients come in as leads. Strikes (automated follow-up sequences) chase generator quotes that went quiet, and Hunts can reach out to past customers on lists you have consent to contact, for example before storm season. See how it works for electrical contractors.
Mako, the AI assistant inside Sharrk, builds your agents, follow-up and campaigns from plain English. Tell it "Answer generator calls, ask about fuel type, home size and panel distance, transfer anyone reporting a safety issue, and book estimates" and it drafts the agent; you approve the changes before anything goes live.
Sharrk Free is $0 with 2,500 one-time credits to build and test agents with Mako, no card needed. Core is $99 a month ($990 a year) with 47,500 credits a month. There are no contracts or setup fees. Start free or schedule a demo.
Related on Sharrk: AI receptionist for electricians, AI answering service, electrician after-hours rates
Sources
- HomeGuide, How much does a whole house generator cost?, no date shown, checked November 2, 2026.
- Fixr, Cost to Install Whole House Generator, updated August 19, 2022, checked November 2, 2026.
- HomeAdvisor, How Much Does a Whole-House Generator Cost in 2025?, no date shown (title says 2025), checked November 2, 2026. HomeAdvisor and Angi are one company and share this data.
- Angi, How Much Does a Whole-House Generator Cost?, updated June 28, 2024, checked November 2, 2026. Shares data with HomeAdvisor.
- This Old House, Generator Buying Guide, updated May 27, 2026, checked November 2, 2026.
- Generac, Portable vs. Home Standby Generators, no date shown, checked November 2, 2026.
- U.S. Consumer Product Safety Commission, As Winter Weather Impacts Millions, CPSC Issues Safety Tips to Help Families Prevent Carbon Monoxide Poisoning and Fires, January 3, 2025, checked November 2, 2026.
- CDC, What to Do to Protect Yourself During a Power Outage, August 26, 2026, checked November 2, 2026.
Frequently asked questions
How much does a whole house generator cost installed?
A whole house generator usually costs about $6,000 to $20,000 installed. HomeGuide puts a typical job at $6,000 to $11,000, Fixr at $10,000 to $20,000 with a $15,000 average, and units over 20 kW can reach $24,000.
How much does a 20 kW or 22 kW generator cost?
The generator alone runs about $4,000 to $6,500 for 17 to 24 kW units, before installation. HomeGuide lists 17 to 20 kW at $4,000 to $6,000 and 22 to 25 kW at $4,500 to $12,000; HomeAdvisor lists 20 to 24 kW at $5,000 to $6,500. Installation is extra.
How much does it cost to install a transfer switch for a generator?
An automatic transfer switch costs about $600 to $2,500, per HomeGuide and HomeAdvisor. Fixr puts the installed total at $2,700 to $3,700 including wiring and labor. For a portable generator, HomeGuide lists a transfer switch at $400 to $1,300 or an interlock at $400 to $850.
Is a portable generator cheaper than a standby generator?
Yes, a portable generator costs $500 to $2,500 versus $3,000 to $6,000 for most standby units before installation, per HomeGuide. A portable must be started, fueled and connected by hand, while a standby starts automatically and runs on natural gas or propane.
How far should a portable generator be from the house?
At least 20 feet. The CPSC says to run portable generators outside only, at least 20 feet from the house, and never in a garage, basement or other enclosed space; the CDC says to keep them 20 feet from any window, door or vent and to use a battery-powered or battery-backup CO detector.