How Much Does Generator Installation Cost in 2026?

A whole-home standby generator installation typically costs $3,000–$15,000 installed, with most homeowners paying around $5,000–$8,000 for a mid-range system. That range sounds wide, but four factors drive almost all of it: generator size, fuel type, transfer switch, and your local labor market.

Here is a full breakdown so you know exactly what to expect before calling a single contractor.

Quick Cost Summary

What You're Getting	Typical Cost
Portable generator + manual transfer switch	$800 – $2,500
10–13 kW standby (essentials only)	$3,000 – $6,000
16–20 kW standby (most of the home)	$5,500 – $9,000
22–26 kW standby (whole home + AC)	$7,500 – $15,000

Prices above include the generator unit, transfer switch, installation labor, and permits. They do not include trenching for gas lines (add $500–$2,000 if needed) or electrical panel upgrades.

The 4 Biggest Cost Drivers

1. Generator Size (kW)

Size is the single biggest variable. Generators are rated in kilowatts (kW). the more of your home you want to power, the larger the unit you need.

Common sizing guide:

7–10 kW. Essentials only: lights, refrigerator, a few outlets, sump pump
13–17 kW. Most rooms plus a small AC unit (1.5–2 tons)
20–26 kW. Whole home including central AC (3–5 tons) and electric range
30–48 kW. Large homes with multiple HVAC zones or a home office with heavy equipment

A licensed electrician or generator installer will perform a load calculation. a list of everything you want backed up and how many watts each draws. Do not skip this step. Oversizing wastes money. Undersizing means the generator trips under load.

2. Fuel Type: Natural Gas vs. Propane vs. Diesel

Most whole-home standby generators run on natural gas or propane. Which one you use depends on what's available at your property.

Natural gas is the most popular choice for urban and suburban homes. It runs off your existing gas line, so you never refuel. Downside: if your gas utility goes down in a major disaster, so does your generator.

Propane is the go-to for rural properties without gas service. You'll need a 250–500 gallon tank installed ($600–$2,500), but you control your own fuel supply. A 500-gallon tank runs a 20 kW generator for roughly 5–7 days at 50% load.

Diesel is common for commercial and industrial generators. Residential diesel installs are less common due to fuel storage regulations and higher unit costs.

3. Transfer Switch Type

A transfer switch is required by code. it prevents backfeed that could injure utility workers during an outage. You have two choices:

Manual transfer switch. cheaper ($200–$600), but you have to physically flip it when the power goes out. Usually paired with portable generators.

Automatic Transfer Switch (ATS). the industry standard for standby generators. It monitors grid power and starts the generator within seconds of an outage. no action needed from you. Adds $500–$1,500 to the project but is included in virtually every standby generator quote.

4. Installation Complexity

Labor typically runs $500–$3,000 depending on:

Gas line run. If the generator is far from your meter or needs a new gas line, add $15–$25 per linear foot of trenching and piping
Electrical panel distance. The further the transfer switch is from your main panel, the more wire run needed
Concrete pad. Most codes require a concrete pad for the generator ($200–$500 if not already present)
Permits. Almost every jurisdiction requires a permit for a standby generator install ($75–$400 depending on city/county)
Panel upgrade. Older 100-amp panels sometimes can't handle the ATS load and need an upgrade to 200 amps ($1,500–$3,000 extra)

Brand Price Comparison

The three dominant brands in the residential standby market are Generac, Kohler, and Cummins. Here's how they stack up on a 20 kW unit:

Brand	Unit Cost (20 kW)	Notes
Generac	$3,500 – $4,500	Most popular, widest dealer network, solid warranty
Kohler	$4,000 – $5,500	Premium build quality, quieter, stronger warranty
Cummins	$4,500 – $6,000	Commercial grade, longest lifespan, fewer dealers
Briggs & Stratton	$2,800 – $3,800	Budget option, smaller dealer network
Champion	$1,500 – $2,500	Entry-level, limited standby lineup

Unit cost does not include installation. Always get quotes with installation included. what looks like a cheaper unit sometimes means a contractor who cuts corners on the electrical work.

What a Real Quote Should Include

When you call a generator installation contractor, a legitimate quote should break out:

Generator unit and model number
Automatic transfer switch (ATS) make/model
Labor for electrical work
Gas line work (if applicable)
Concrete pad (if needed)
Permit fees
Warranty terms. most manufacturers offer 5 years on parts, some include labor

Be cautious of any quote that's a single lump number with no line items. You want to know what you're paying for.

How to Save Money on Installation

Get at least 3 quotes. Labor rates vary 20–40% between contractors in the same city. The first quote is rarely the best one.

Time your purchase. Generator demand spikes after major storms. Buying in spring or early summer (before hurricane season) often means better availability and more competitive pricing.

Bundle with an electrical panel upgrade. If your panel needs upgrading anyway, doing it at the same time as the generator install saves a separate mobilization cost.

Check for utility rebates. Some utilities offer rebates for standby generators as part of demand-response programs. Ask your contractor if any apply in your area.

Ask about financing. Most generator installers offer 12–24 month financing through GreenSky or similar programs. A $7,000 system at 0% for 18 months is $389/month. roughly what one extended power outage would cost in hotel bills, spoiled food, and lost work.

Is a Whole-Home Generator Worth It?

For most homeowners in storm-prone areas. Texas, the Southeast, the mid-Atlantic. the answer is yes. A single 3-day outage can cost $1,500–$4,000 in spoiled food, hotel stays, generator rental, and lost productivity. Two outages and you've paid for the unit.

The more relevant question is what size to get. Most contractors will try to sell you more capacity than you need. Do the load calculation honestly, decide which circuits actually matter to you during an outage, and size accordingly.

Get a Free Quote in Your City

The fastest way to know what it will actually cost in your area is to get 2–3 local quotes. Labor rates, permit costs, and gas line requirements vary significantly by city and county.