What goes into whole-house generator installation cost
For a permanent standby, the generator itself ($2,600–$7,000 street) is frequently less than the install work around it. A portable is the opposite — cheap and self-installed, but you trade automatic cutover and continuous runtime for a lower price. Here's the honest breakdown of a typical standby job:
| Line item | Typical range |
|---|---|
| The generator unit (10–24kW street price) | $2,600 – $7,000 |
| Automatic transfer switch (ATS), if not bundled | $400 – $1,200 |
| Electrical labor (wiring, ATS tie-in, licensed) | $1,500 – $4,000 |
| Gas hookup — short NG run | $500 – $1,500 |
| Gas hookup — long / upsized run or new propane tap | $1,500 – $4,000 |
| Concrete / composite pad | $200 – $900 |
| Electrical panel upgrade (if service is undersized) | $1,500 – $3,500 |
| Permit & inspection | $100 – $600 |
Standby vs portable: the cost fork
Portable ($900–$1,600 for the unit) needs no professional install — you buy it, roll it out, and run cords or add an interlock/inlet kit ($200–$600 if you want to backfeed a few circuits). No permit for the unit itself in most areas, no gas line, no pad. The trade: you start it by hand, refuel every 8–11 hours, and it's louder. Standby is the expensive path precisely because it's automatic and whole-house — the ATS senses an outage and switches in seconds, and it runs continuously on utility gas. That automation is the money: transfer switch, gas plumbing, a pad, and a licensed electrician are the cost, not the box.
The big cost traps
The gas line is the wildcard. A short run from an existing meter is cheap; a long run across the yard or an upsized meter to feed a 24kW unit can add $2,000–$4,000 and it's rarely quoted upfront. ATS may not be included. Several base standby SKUs (e.g. Generac 7226/7224/7171, Cummins RS20A, Briggs 040657) ship without a transfer switch — you buy it separately, so confirm before you compare quotes. Panel upgrades bite older homes. If your service is undersized for a whole-house switch, add $1,500–$3,500. Bigger isn't free. Jumping from 14kW to 24kW raises both the unit and the gas/electrical work — size for your real load, not the biggest box.
How big a generator do I need?
Rough sizing (this is what the calculator uses to pick a unit): essentials — fridge, furnace, some lights — run on ~10kW. A 2,000 sq ft home wanting most of the house runs ~12–14kW. A 3,000 sq ft home adding central AC and a well pump wants ~18–20kW. A 4,000+ sq ft / 200-amp whole-house switch typically means a 22–24kW+ unit with a service-rated ATS. Remember the honest-watts caveat: a "24kW" unit is 24kW on propane but closer to ~21kW continuous on natural gas — size to the NG number, which is what most permanent installs actually run.
Frequently asked
How much does a whole house generator cost installed?
For a typical residential standby, plan on roughly $7,000–$18,000 all-in. A modest 10–14kW unit on an existing short gas line lands near the low end; a 22–24kW whole-house unit with a long gas run, panel upgrade and metro labor pushes the high end. The unit is usually 30–50% of the total — the rest is transfer switch, gas, pad, electrical labor and permits.
Why is standby generator installation so expensive?
Because you're paying for automation and code compliance, not just the box: a licensed electrician ties in an automatic transfer switch, a plumber runs and (often) upsizes the gas line, you pour a pad, and the job is permitted and inspected. That work commonly runs $3,000–$6,000+ on top of the generator itself.
Is a portable generator cheaper than a standby?
Much cheaper upfront — $900–$1,600 for the unit and little-to-no install. The trade-offs are manual start, finite tank runtime (8–11 hours at half load), more noise, and no automatic cutover. If you want lights-and-fridge insurance for occasional outages, a portable plus an interlock kit is the budget path; if you want the whole house to ride through a multi-day storm untouched, that's what a standby's install cost buys.
Does the price include the transfer switch?
Not always. Some standby SKUs bundle an ATS (Generac 7210, Kohler RCAL variants, Champion aXis 100837); many base SKUs do not. A separate ATS runs about $400–$1,200 plus wiring labor. Always confirm whether a quoted "generator price" is unit-only or includes the switch.
Cost figures are reasoned ranges from manufacturer install guides, contractor cost surveys, and the verified unit prices in our generators dataset (spec-verified Aug 2026) — not a quote for your specific job. Actual bids vary with gas-line distance, service size, permitting jurisdiction and local labor. This is an educational estimate; get itemized local quotes before you commit. Some product links may be affiliate; that never changes the numbers.