Whole-House Generator Cost 2026

It depends on what you want to power. A 7-10 kW unit covers essentials (refrigerator, furnace, some circuits) for $6,500-$9,000 installed. A 12-16 kW unit powers most homes including HVAC for $8,000-$12,000. Large homes that want everything running need 18-26 kW units at $11,000-$18,000+. A reputable installer calculates your load based on the appliances and systems you want to back up, rather than guessing by square footage.

Natural gas is usually more convenient and cheaper to run if you already have a gas line — the generator draws fuel continuously without refueling. Propane is the option when natural gas isn't available; it requires a tank ($500-$2,500 to buy or lease) but stores well and burns clean. Natural gas setups are typically cheaper to install if the line is close and adequately sized; propane adds tank costs. Your installer will recommend based on your home's existing fuel infrastructure.

An automatic transfer switch (ATS) is the device that detects a power outage and automatically starts your standby generator, switching your home from the grid to generator power without you doing anything — then switches back when grid power returns. It's required for a standby generator and included in most full installations. The ATS is what separates a permanently installed standby generator (automatic, hands-off) from a portable generator you have to manually connect.

Usually because of installation factors beyond the unit itself. The most common cost-drivers are distance from the gas line and electric meter (more trenching, piping, and wiring), a gas line that needs extending or upsizing ($500-$2,000+), an electrical panel upgrade in older homes ($1,500-$4,000), or a propane tank if you lack natural gas. Larger kW units and difficult placement also add cost. Ask for an itemized quote separating equipment, electrical, gas, and the transfer switch.

For homeowners in outage-prone areas — or with medical needs, sump pumps, well water, or frequent remote work — a standby generator is often worth it for the security and convenience of automatic, whole-home backup power. It also adds resale appeal. The payback is less about money and more about avoiding spoiled food, frozen pipes, flooded basements, and disruption during outages. In storm-prone regions like the Gulf Coast and hurricane belt, demand and perceived value are highest.