Furnace Replacement Cost Calculator: 2026 Installed Prices

A standard-efficiency (80% AFUE) gas furnace replacement runs $3,700-$6,200 installed in 2026 depending on size, with a typical 80,000 BTU unit landing around $4,100-$5,200 at national-average labor. Step up to a 96% AFUE two-stage model and the same job runs $4,900-$6,200; a top-tier modulating furnace runs $5,900-$7,600. The calculator above prices your exact size, tier, and region.

A like-for-like furnace swap - new unit in the same spot, existing gas line, venting, and ducts reused - is the $3,700-$6,200 range most homeowners pay. A first-time installation costs more because of the extras: running a gas line, adding flue or PVC venting, a condensate drain for high-efficiency models, and any ductwork changes. Duct sealing and modifications add roughly $2,000, and a full duct replacement adds $6,500 or more - use the ductwork option in the calculator to price it.

About $4,700 installed for the most common job: an 80,000 BTU, 80% AFUE single-stage gas furnace at national-average labor, including equipment, labor, permit, and disposal of the old unit. The unit alone typically accounts for roughly half of that; the rest is labor, materials, and permit fees. Prices swing from about $4,000 in lower-cost rural markets to $6,300+ in the most expensive metros for the same furnace.

Three moves matter most. First, always get a bid from a smaller local operator alongside the big-name companies - low-overhead shops routinely install the same tier of furnace for thousands less, and homeowners report complete installs under $3,000 from two-truck operations. Second, buy in the shoulder season (spring and fall), when discounts of 10-15% are common. Third, don't over-buy the tier: a 96% AFUE two-stage furnace only pays back its premium in cold climates. Use this calculator's number as your fair-price anchor and make every quote explain its distance from it.

Plan on $4,900-$6,200 installed for a typical 80,000 BTU two-stage 96% AFUE furnace - roughly $900-$1,000 more than the equivalent 80% AFUE model. In cold climates that premium usually pays back through fuel savings within the furnace's life; in mild-winter regions the payback is much slower. High-efficiency models also need PVC venting and a condensate drain, which is included in a professional quote but adds work in some retrofits.

Electric furnaces are cheaper up front - there's no gas line, combustion venting, or flue work - but they cost far more to run in most of the US because electric resistance heat is expensive per BTU. This calculator prices gas furnaces, the most common replacement. If you're going electric, compare a heat pump first: it delivers 2-3x the heat per dollar of electricity and is priced in our HVAC replacement cost calculator.

The two big-ticket furnace repairs are a blower motor at $450-$1,500 and a cracked heat exchanger at $2,000-$3,500 - and a bad heat exchanger almost always means replace the furnace, since the repair approaches a new unit's price. Use the $5,000 rule: multiply the repair quote by the furnace's age in years; over $5,000, put the money toward replacement. A $500 igniter repair on a 6-year-old furnace is worth it - the same money into an 18-year-old unit usually isn't.

If both are within a few years of the same age, usually yes - a combined furnace + AC replacement saves about 10% versus two separate jobs, because one crew handles both in a single visit with one permit. The evaporator coil also sits on top of the furnace, so pairing new equipment keeps everything matched. Price the combo with our HVAC replacement cost calculator, which covers full furnace + AC systems and heat pumps.

Size first, price second - an oversized furnace costs more up front and short-cycles for its whole life. Furnace capacity is quoted in input BTUs (60,000, 80,000, 100,000, 120,000), driven by your home's square footage, climate, and insulation. Run your numbers through our furnace size calculator, then bring that BTU size back here to price the replacement.

It short-cycles - firing hard, overshooting the thermostat, and shutting off in minutes - which means uneven room temperatures, more noise, higher gas bills, and early wear on the heat exchanger, the one part whose failure totals the furnace. Worse, there's usually no recourse after installation: contractors rarely refund the difference once an oversized unit is in, and homeowners stuck with one face a costly downsizing. Protect yourself before signing - verify the BTU size with our furnace size calculator or a whole-house load calculation, and be suspicious of any quote that sizes 'up to be safe.'

Yes - contractor financing is standard, and at 2026 rates a typical $4,700 furnace replacement runs about $61/month on a 10-year loan at 9.9% APR (the calculator shows the monthly figure for your exact configuration). Watch 'same as cash' promotional periods: they're genuinely free if paid off in time, but deferred interest is brutal if not.