Generator installation cost: 2026 price guide
A whole-house standby generator installed costs $5,000 to $12,000. A portable generator setup with a transfer switch runs far less, at $800–$2,500.
Generator cost splits into two very different projects. A portable generator just needs a transfer switch so you can safely power select circuits without backfeeding the grid — a relatively small job. A whole-house standby unit is a permanent installation: a dedicated pad, an automatic transfer switch, a gas or propane line, and utility coordination.
If the job also requires panel work, see our Electrical Panel Upgrade Cost guide.
Why you need a transfer switch
By system type
Generator install cost by type
Equipment and installation labor; the generator unit itself is often the largest line item on standby systems.
| System | Typical range | Average |
|---|---|---|
| Manual transfer switch only | $500 – $1,200 | $850 |
| Portable generator + switch (installed) | $800 – $2,500 | $1,600 |
| Standby generator, small home (10–14kW) | $5,000 – $8,000 | $6,500 |
| Standby generator, large home (20kW+) | $9,000 – $15,000+ | $11,500 |
| Gas/propane line run | $500 – $2,000 | $1,000 |
| Annual maintenance service | $150 – $400 | $275 |
Price factors
What drives the price up or down
System size (kW)
Whole-home coverage (including AC) requires a larger, pricier unit than a system sized just for essential circuits.
Fuel source & line run
Natural gas or propane standby units need a gas line run to the unit’s pad — distance and existing gas service capacity affect cost.
Permits & utility coordination
Standby generators typically require electrical and gas permits, plus a utility inspection before activation.
Panel capacity
An older or undersized panel may need an upgrade to properly integrate an automatic transfer switch.
Common questions
Frequently asked questions
No — this “backfeeding” is dangerous and illegal in most areas. It can send power back through the grid and electrocute utility line workers who assume the lines are dead. A transfer switch is required to isolate your home from the grid before the generator powers anything.
A load calculation from an electrician determines this based on which circuits you want covered. Essentials-only (fridge, well pump, some lights) might need 10–14kW; whole-home coverage including central AC often needs 20kW or more.
The physical install typically takes 1–2 days, but the full timeline including permits, gas line coordination, and the required utility inspection often runs 2–6 weeks start to finish.
Need an installer quote?
Connect with a licensed electrician to run a load calculation and get a realistic, itemized price.