New Furnace Cost (2026): Installed Guide

By HomeCost Guide · Updated October 2026 · complete installed cost for a standard gas furnace replacement, per Forbes Home and Angi

A new furnace costs $2,800 to $10,000 installed for most American homes, with a national average around $4,800 according to published data from Forbes Home and Angi. That figure covers the complete job — the furnace unit itself, professional installation, removal of the old equipment, and permits — not just the box. Where you land in the range comes down to fuel type (gas is most common, electric cheapest to install, oil the priciest), efficiency rating (an 80% AFUE workhorse versus a 96%+ high-efficiency model), and your home's size, which dictates the BTU capacity you need. A straightforward gas furnace swap in a ranch home can come in under $4,000; a high-efficiency modulating unit with ductwork modifications in a large two-story can clear $9,000. This guide walks through complete installed costs by furnace type, what labor should include, and how to read a quote like a pro. You'll also find the federal tax credits and utility rebates that can shave hundreds off a high-efficiency install, and the seasonal timing trick that routinely saves 10–20%.

1. New Furnace Cost (2026): Installed Guide cost breakdown

The 80% versus 95%+ AFUE decision is the classic value question: the high-efficiency unit costs $1,500–$3,000 more upfront but converts nearly all its fuel to heat instead of venting 20% up the flue. In cold climates with $200+ winter gas bills, the payback is typically 5–8 years; in mild climates, the 80% unit usually wins on total cost. Ask any bidder to show the payback math for your climate — it's simple arithmetic, not a judgment call.

Where the money goes: labor vs materials vs fees

• Furnace unit$1,500–$5,500The equipment itself: $1,500–$2,500 for a basic 80% gas unit, $2,500–$4,500 for a two-stage 95% model, $4,000–$5,500+ for modulating high-efficiency units. Electric furnaces run $800–$2,000 for the unit alone — cheap to buy, expensive to run.
• Installation labor$1,000–$2,500A straightforward like-for-like swap takes a crew most of a day. Costs rise with difficult access (tight attics, crawlspaces), venting changes for high-efficiency upgrades, and gas or electrical modifications.
• Old furnace removal and disposal$50–$500Haul-away is usually folded into the quote. Standalone removal runs $100–$300; oil tanks or asbestos-wrapped ductwork (common in pre-1980 homes) push disposal costs much higher.
• Permits and inspections$100–$400Most jurisdictions require a mechanical permit and inspection for furnace replacement. Your contractor should pull it — confirm it's in the quote rather than appearing later as an add-on.
• Ductwork modifications$500–$2,000New furnaces sometimes need plenum or duct transitions, and high-efficiency upgrades may require new PVC venting and condensate drains. Full duct replacement is a separate $3,000–$7,500 project — don't let it hide inside a furnace quote.

Sources: Forbes Home, HomeAdvisor, Angi, This Old House. Figures are national averages compiled from published industry data; your price will vary by home and location.

2. Signs you need a new furnace

Signs you need a new furnace

• Age 15–20+ years — the typical service life of a gas furnace, after which efficiency and reliability fall off.
• Heating bills climbing year over year with no change in rates or thermostat habits.
• Frequent repairs — two or more service calls in a single heating season is the classic replacement signal.
• Uneven heating: some rooms roasting while others stay cold, beyond what duct balancing can fix.
• Strange noises — banging, rattling, or squealing from the blower or burner assembly that repairs don't resolve.
• Yellow or flickering burner flame (should be blue) or a tripping carbon monoxide detector — safety issues needing immediate attention.

3. How new furnace installation works

How new furnace installation works

1. Load calculation and sizing. The contractor performs a Manual J load calculation — measuring your home's heat loss through walls, windows, and infiltration — to determine the correct BTU capacity. Rule-of-thumb sizing (square footage × a factor) routinely oversizes equipment; insist on the real calculation.
2. Equipment selection. You choose fuel type, efficiency (AFUE), and staging (single-stage, two-stage, or modulating) matched to your climate and budget. The contractor confirms the unit physically fits the existing space and venting.
3. Permit and scheduling. The contractor pulls the mechanical permit. Most installs are scheduled 1–3 weeks out — or same-week in heating season if your old unit died, often at premium pricing.
4. Removal of old equipment. Gas and power are disconnected, the old furnace is removed, and the area is prepped. Refrigerant lines stay untouched (that's the AC side); ductwork connections are inspected for reuse.
5. Installation and venting. The new furnace is set, connected to supply and return ductwork, gas line, venting, condensate drain (high-efficiency models), and thermostat wiring. High-efficiency upgrades get new PVC intake/exhaust venting through a sidewall.
6. Commissioning and testing. The technician fires the unit, checks gas pressure, temperature rise across the heat exchanger, and airflow, then walks you through the thermostat and filter schedule. The inspector signs off on the permit — get the signed card for your records.

4. What affects the cost

Fuel type

Gas furnaces dominate and hit the value sweet spot: $2,800–$8,000 installed, with the cheapest fuel cost per BTU in most regions. Electric furnaces are cheapest to install ($2,000–$4,500) but cost 2–3x more to operate — sensible only in mild climates or homes without gas service. Oil furnaces ($4,500–$9,000) persist in the Northeast, but oil's price volatility makes fuel-switching to gas worth pricing where a line is available. Your fuel decision locks in a decade-plus of operating costs.

AFUE efficiency rating

Annual Fuel Utilization Efficiency measures how much fuel becomes heat: 80% AFUE wastes 20 cents of every fuel dollar up the flue; 96% wastes 4 cents. The price steps are real — about $1,500–$2,000 more per efficiency tier — and so are the savings. In cold climates, a 95%+ unit typically pays back its premium in 5–8 years; in mild climates it may never pay back, making the 80% unit the rational buy. Federal tax credits under 25C can shave up to $600 off qualifying high-efficiency installs.

BTU sizing and home size

Furnaces are sized in BTUs — typically 40,000 to 120,000 for residential — and the unit price steps up $300–$600 per 20,000 BTU tier. But bigger is not better: an oversized furnace short-cycles (rapid on-off), which wastes fuel, wears components, and heats unevenly. Correct sizing comes from a Manual J calculation, not square-footage rules of thumb. A contractor who sizes from the existing unit's label without checking is perpetuating whatever mistake was made last time — possibly decades ago.

Single-stage vs two-stage vs modulating

Single-stage furnaces run full-blast or off — cheapest ($2,800–$5,000 installed) but least comfortable. Two-stage units run at ~65% most of the time, kicking to full only in deep cold: $1,000–$2,000 more, noticeably more even heat. Modulating furnaces adjust in tiny increments for the most consistent temperatures: premium pricing ($5,500–$10,000) for premium comfort. The comfort difference is real and immediately noticeable; whether it's worth the premium depends on how much you value eliminating temperature swings and cold spots.

Ductwork condition

A new furnace connected to leaky, undersized, or uninsulated ductwork is like a new engine in a car with flat tires — the equipment can't deliver its rated efficiency. Duct modifications for a proper fit run $500–$2,000; sealing leaky ducts adds $1,000–$3,000; full replacement is $3,000–$7,500. In homes where some rooms never heat properly, the ducts — not the furnace — are often the real problem, and fixing them can let you buy a smaller, cheaper furnace.

Venting requirements

Standard 80% furnaces use the existing metal flue; upgrading to 90%+ efficiency requires new PVC intake and exhaust venting, plus a condensate drain and pump — typically $500–$1,200 in added labor and materials. If the old flue is shared with a water heater, the water heater may need re-venting too (another $300–$800). Chimney liners for oil-to-gas conversions add $1,000–$2,500. Venting is the most common source of 'unexpected' upcharges, so pin it down in the quote.

Gas line and electrical work

Most replacements reuse the existing gas line, but fuel switches (oil to gas, or adding gas service) need a new line at $500–$2,000, plus the utility's meter set fee. Electric furnaces may demand a panel upgrade if the service is only 100 amps — a $1,500–$3,000 job that dwarfs the furnace premium. High-efficiency gas units need a 120V outlet and condensate pump wiring, usually minor. Ask explicitly what fuel and electrical work the quote assumes; these are the line items most likely to appear as surprise change orders.

Brand tier and warranty

Equipment brands cluster into budget, mid-tier, and premium lines with $1,000–$2,500 separating installed prices for comparable specs. The dirty secret of the industry: reliability differences between major brands are modest — installation quality matters far more. What does differ meaningfully is warranty: 10-year parts is standard on mid-tier+, with some premium lines offering lifetime heat-exchanger coverage. Weight the installer's reputation and the warranty terms more heavily than the badge on the cabinet.

Timing and season

Furnace replacements in October–November (shoulder season) routinely price 10–20% below January emergency installs, when demand peaks and technicians are booked solid. A planned replacement also lets you collect three quotes calmly instead of accepting the first available crew at whatever price they name. If your furnace is limping through its 18th winter, the cheapest install is the one you schedule in fall — not the one you need at 2 AM in a cold snap.

Local labor rates and code requirements

HVAC labor runs $75–$150 per hour depending on market, and a full install is 6–10 labor hours — so geography alone swings quotes $500–$1,000. Local codes add their own costs: seismic strapping in California, condensate freeze protection in northern states, combustion-air requirements in tight new homes. Urban permit fees and inspection scheduling can add days to the timeline. National averages are a compass, not a price tag — three local quotes are the real number.

5. Saving money & hiring right

Questions to ask your contractor

• Will you perform a Manual J load calculation, or are you sizing from the old unit?
• What AFUE and staging does this quote include — and what's the payback math for my climate?
• Exactly what's included: removal, venting changes, permits, thermostat, condensate drain?
• Is the ductwork adequate for this unit, or are modifications needed? At what cost?
• What are the parts and labor warranty terms, and who honors the labor warranty if you close?
• Are there utility rebates or federal tax credits this equipment qualifies for?

6. How costs vary by state

Furnace costs follow both labor rates and climate: cold northern states buy higher-efficiency units (raising averages) at higher labor rates, while southern states install cheaper equipment less often. Fuel mix matters too — oil-dominated New England pays the most per install.

7. Frequently asked questions