2026 buying & installation guide
How much does a whole-house generator actually cost?
Published 2026 consumer cost guides put many standby-generator projects in a broad range of roughly $1,500 to $9,000, while larger whole-home systems and complex installations can run well above that. The useful number is not a single national average—it is the equipment price plus the specific work your property requires.
Direct answer
The generator on the pallet is only part of the bill.
HomeAdvisor and Angi currently report an average around $5,160 with a typical range of about $1,516–$8,810, but their own breakdowns show that generator size, installation complexity, transfer equipment, fuel work, pad/site work and permits move the total. Other current guides place typical 18–26 kW whole-home installations substantially higher. Treat national ranges as budgeting references—not a prediction of your quote.
Real equipment benchmarks
Start with manufacturer-published MSRP, then build the installation around it.
These are current manufacturer-published starting MSRPs for selected residential models. They are useful anchors because they separate verifiable equipment pricing from installation estimates. Package contents differ: an ATS may be included on one model and sold separately on another.
| Brand | Model | Published output | Starting MSRP* |
|---|---|---|---|
| Kohler / Rehlko | 10RESV | 10 kW | $3,834 |
| Kohler / Rehlko | 14RCA | 14 kW LP / 12 kW NG | $4,997 |
| Briggs & Stratton | PowerProtect 18kW | 18 kW NG / LP | $5,746 |
| Kohler / Rehlko | 20RCA | 20 kW LP / 18 kW NG | $5,813 |
| Briggs & Stratton | PowerProtect 22kW | 22 kW NG / LP | $6,037 |
| Briggs & Stratton | PowerProtect+ 26kW | 26 kW LP / 24 kW NG | $7,336 |
| Kohler / Rehlko | 26RCA | 26 kW LP / 24 kW NG | $7,445 |
*Manufacturer starting MSRP as displayed on current product pages; installation, shipping, accessories and ATS may be extra depending on model/package. Dealer pricing can differ.
Where the rest of the money goes
Six cost buckets explain most quote differences.
Generator + ATS
The advertised generator price may or may not include an automatic transfer switch. Compare the exact model and package—not just the kW number.
Electrical scope
Service size, panel condition, ATS configuration, conduit distance, load-management modules and panel upgrades can change the electrical portion substantially.
Natural gas or propane
Pipe length, gas-meter/regulator capacity, propane storage and required fuel flow at full load can turn a simple hookup into a larger project.
Site work
Pad type, trenching, grading, landscaping, delivery access and distance from the electrical/fuel connection points all affect labor and material.
Permits + inspections
Electrical, fuel-gas, building, zoning and utility requirements vary by jurisdiction. A national cost number cannot price your local permit path accurately.
Climate + accessories
Cold-weather kits, battery heaters and other model-specific accessories matter in northern climates and should appear in the scope when required.
2026 installation benchmarks
Why you will see very different “average” prices online.
Current published guides use different datasets and definitions. HomeAdvisor/Angi report about $5,160 average and $1,516–$8,810 typical total. Estimatool describes roughly $6,000–$12,000+ installed. A recent independent guide using manufacturer listings and multiple installer-cost sources puts many homes around $9,000–$16,000 installed. Those figures are not interchangeable: some datasets include smaller systems, and site complexity and region can dominate the installation side.
Quote comparison checklist
Make every contractor price the same job.
A cheap-looking proposal can simply exclude work. Before comparing totals, check these ten lines.
Natural gas vs propane
Fuel choice changes both installation and operating assumptions.
Natural gas can avoid on-site fuel storage, but the existing meter, regulator and piping still have to support the generator's required fuel flow. Propane requires correctly sized storage and adequate vaporization in cold weather. Do not choose a fuel solely from a national cost-per-day table; local utility rates, propane prices, tank ownership and the exact generator fuel-consumption curve matter.
Generator size
Square footage alone does not size a standby generator.
Large starting loads—air conditioners, heat pumps, well pumps and other motors—can matter more than the number of rooms. Load management can sometimes let a smaller generator serve a larger home by preventing selected loads from starting simultaneously. Use a load calculation and model-specific motor-starting capability before turning a cost table into a sizing decision.
Frequently asked cost questions
Is a transfer switch included in the generator price?
Sometimes. It is package- and model-specific. For example, Kohler's current 26RCA page shows an ATS included, while its 20RCA page lists the ATS separately. Verify the exact SKU and scope.
Why can two quotes for the same generator differ by thousands?
Fuel-line distance, panel/service work, ATS configuration, trenching, site access, permit requirements, accessories and excluded work can all differ even when the generator model is identical.
Is a 22–26 kW generator automatically a whole-house generator?
No. Whether it covers the whole house depends on the actual connected loads, fuel rating, starting loads and load-management strategy—not the marketing label alone.
Should I buy the generator online and hire someone to install it?
Compare the complete economics first. Confirm installer willingness, freight/damage responsibility, ATS compatibility, startup/commissioning, warranty registration and who owns any equipment problem before buying separately.
How much should I budget for maintenance after installation?
Maintenance is a recurring ownership cost and varies by brand, engine, run hours and local labor. Our maintenance section separates model-specific schedules rather than applying one annual number to every generator.
What is the best way to lower installation cost?
Reduce avoidable complexity, not safety: choose a viable placement near appropriate fuel/electrical connection points, size from actual loads, evaluate load management, and compare itemized scopes from qualified installers.
Next step
Now understand the installation behind the price.
Placement, fuel, ATS design, permits and commissioning are where an online equipment price becomes a real project.