HVAC Replacement Cost Calculator

How the HVAC replacement cost calculator works

Most HVAC quotes are built from the same parts: the equipment, the labor to remove the old system and set the new one, and a handful of add-ons. This calculator follows that structure.

1. Size. It suggests an AC or heat pump size in tons from your square footage and climate, and a furnace size in BTU. You can override either one if you already know your size. For a closer sizing estimate, use our AC tonnage calculator.
2. Base price. It looks up the typical US installed price for that system and size. Central AC prices match our AC replacement cost guide. Gas furnace prices match our furnace replacement cost guide.
3. Efficiency. High-efficiency and premium equipment cost more up front, so the price is scaled for the level you pick.
4. Add-ons. Ductwork, electrical work, a new line set, a permit and other extras are added as separate lines.
5. Region and timing. Everything is adjusted for your region, and the labor portion goes up for peak-season or emergency installs.
6. Rebates. Any rebate you enter comes off the low, likely and high prices.

The "likely" price sits a little below the middle of the range, because most homes don't need everything that pushes a job to the top. Treat the high end as a warning sign. If a quote lands above it, ask what's driving the price.

New HVAC system cost by type and efficiency

These are typical US installed prices for a 3-ton system and an 80,000 BTU furnace, before ductwork, permits and extras, at the national average. Use the calculator for your own size and region.

Replacing the AC and furnace together costs less than two separate jobs. One crew, one trip and one permit cover both, so the calculator takes 8% off the combined equipment price. A matched indoor coil and outdoor unit also have to be replaced together to get the rated efficiency, which is why AC-only prices include the coil.

A ducted heat pump replaces both your AC and, in most climates, most of your furnace use. If your furnace is still young, a dual-fuel setup keeps it as backup for the coldest days. Our heat pump vs. furnace guide compares them.

Efficiency levels: SEER2, HSPF2 and AFUE explained

SEER2 measures cooling efficiency for ACs and heat pumps. It's the cooling delivered over a season divided by the electricity used, under a test that took effect in 2023. Higher is better. Federal minimums for new split systems are 13.4 SEER2 for central ACs in the North and 14.3 SEER2 for most sizes in the South and Southwest, and 14.3 SEER2 for heat pumps everywhere. HSPF2 is the matching heating rating for heat pumps, with a federal minimum of 7.5. AFUE is the share of a furnace's fuel that becomes heat in your home. An 80% furnace loses 20% up the flue.

The Department of Energy has a rule on the books that would require new gas furnaces made after December 18, 2028 to reach 95% AFUE. It's being challenged in court and its date could change, so for now 80% furnaces can still be sold and installed. A 95% furnace vents through plastic pipe and drains water, so switching from an 80% unit often adds venting work and sometimes a condensate pump.

Two-stage and variable-speed units also run longer at low speed. That gives quieter operation, more even temperatures and better humidity control, which matters as much as the energy savings in humid climates.

How we calculate the price and the 10-year cost

Line item = (equipment share × price + labor share × price × timing) × region
Low / high = sum of line items − rebates
Likely = low + 0.45 × (high − low)
Cooling kWh/yr = tons × 12,000 × cooling hours ÷ SEER2 ÷ 1,000
Furnace therms/yr = heat needed ÷ AFUE ÷ 100,000
Heat pump kWh/yr = heat needed ÷ (HSPF2 × 1,000) × cold-climate factor
10-year cost = likely price + 10 × yearly energy cost

Cooling hours are 2,600 (hot), 2,000 (warm), 1,400 (mixed), 1,000 (cool) and 700 (cold). Heat needed per year is 6,000 to 36,000 BTU per square foot, from hot to cold climates. Heat pumps get a 10% penalty in cool climates and 25% in cold ones, because they work harder in deep cold. Dual-fuel systems use the heat pump for 70% of the heat and the furnace for 30%.

Worked example (the default settings): a 2,000 sq ft home in a mixed climate, AC plus gas furnace, standard efficiency, national average prices. The suggested AC is 3.5 tons ($4,600–$8,600). The house needs about 2,000 × 35 = 70,000 BTU of furnace output, and at 80% AFUE that is 87,500 BTU of input, so the calculator picks a 100,000 BTU furnace ($3,800–$6,900 × 1.06 = $4,028–$7,314). The 8% bundle saving takes off $690–$1,273. A permit ($100–$500) and haul-away ($100–$300) bring the total to $8,138–$15,441. The likely price is 8,138 + 0.45 × 7,303 = $11,424, shown rounded as $11,400.

For energy, cooling uses 3.5 × 12,000 × 1,400 ÷ 14.3 ÷ 1,000 = 4,112 kWh, or $740 at $0.18. Heating uses 2,000 × 20,000 ÷ 0.80 ÷ 100,000 = 500 therms, or $750 at $1.50. That's about $1,490 a year and $26,326 over 10 years including the install. These are rough averages to compare levels, not a bill forecast.

What else changes the cost to replace an HVAC system

Ductwork

Reusing sound ducts costs nothing extra. Sealing leaky joints runs about $0.35–$1.00 per square foot of house. Replacing part of the system, such as one floor or the attic runs, is about $1.25–$3.00 per square foot. A full duct replacement runs about $3.50–$7.00 per square foot, or $7,000–$14,000 for a 2,000 sq ft home. Ask for a duct leakage test if rooms are uneven or the old ducts are crushed or disconnected.

Electrical, line set and other extras

A heat pump or bigger AC may need a new circuit and outdoor disconnect ($350–$900). An all-electric heat pump with backup heat strips can push an older 100-amp service past its limit, so a panel upgrade ($1,500–$4,000) is common there. Newer systems use A2L refrigerants such as R-454B and R-32, and many installers replace the copper line set rather than reuse an old one ($600–$1,500).

Region and timing

Labor rates drive most regional differences. We adjust prices by about −10% in the South, −7% in the Midwest, +2% in the Mountain West, +18% in the Northeast and +20% on the West Coast. Replacing a system in July or January, or after a breakdown, costs more. You have less time to compare quotes and crews are booked. The calculator adds 15% to labor for peak season and 35% for an emergency install. If your system is aging, replace it in spring or fall.

Tax credits and rebates in 2026

The federal 25C credit is gone for 2026 installs. The Energy Efficient Home Improvement Credit used to pay 30% of the cost of a qualifying heat pump (up to $2,000) or a high-efficiency AC or furnace (up to $600). The July 2025 tax law ended it for property placed in service after December 31, 2025. According to the IRS, the date that counts is when installation is finished, not when you paid. A system installed in 2026 does not qualify, even if you put down a deposit in 2025.

What's still available:

• Utility rebates. Many electric and gas utilities offer $100 to $1,500 or more for heat pumps, high-efficiency equipment or smart thermostats. Check your utility's website before you sign.
• State heat pump rebates (HEEHRA). The federal home electrification rebate program is run by the states and is limited to households under 150% of area median income. It pays up to $8,000 toward a heat pump for lower-income households where a state program is open. Some states have launched, some haven't, and some have run out of funds.
• Manufacturer promotions. These are common in spring and fall, and the contractor usually applies them.

Enter the total you expect in the rebates box of the HVAC replacement cost calculator. It comes off every price on this page.

How to get a fair quote on a new HVAC system

• Get two or three quotes and compare each one with the HVAC replacement cost calculator, using the same scope: size, efficiency, ductwork and extras. Use the line-item breakdown above as a checklist.
• Ask for a load calculation. A contractor who sizes from your old unit's label may sell you the wrong size. Oversized systems short cycle and leave the house humid.
• Check the matchup. The outdoor unit and indoor coil or air handler should be a matched, rated combination, or you won't get the efficiency you paid for.
• Read the warranty. Many brands give 10 years on parts only if you register within 60 to 90 days. Labor warranties vary by installer.
• Don't replace a working system in a panic. If the problem is a capacitor or contactor, a repair may buy you years. Start with the HVAC problem finder.

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