How much does a new gas furnace cost?

Prices checked October 2026. Wages: BLS, May 2025.

A condensing furnace costs a bit more to install than a standard one, but in an old house the venting usually decides the final number. The range above covers a new gas furnace in six configurations: 60,000, 80,000 or 100,000 BTU input, each at either 80% efficiency (non-condensing, vented through metal flue pipe) or 95% and up (condensing, vented through plastic pipe). Furnace prices come from current listings at public online retailers. Installation is the Department of Energy's average from its 2023 furnace rule, covering labor, materials, removal of the old furnace and typical permit costs. The labor part, a bit over a quarter of that average in DOE's breakdown, is scaled to HVAC technician wages in your metro or state.

DOE's figure for a 95% furnace is somewhat higher than for an 80% unit, because condensing furnaces need plastic exhaust pipe, often an intake pipe too, and a condensate drain. The bigger swings come from venting problems in older houses. Picture a worn vent connector, a chimney that needs a liner, or a water heater left alone in a chimney sized for two appliances. Those show up below the estimate as separate lines, so you can see whether a quote includes them.

Installed price by size, national

Size	Unit (list)	Low	Typical	High
60,000 BTU, 80% efficiency	$1,221	$3,650	$4,100	$5,400
60,000 BTU, 95%+ efficiency	$1,606	$4,350	$4,750	$5,750
80,000 BTU, 80% efficiency	$1,162	$3,750	$4,050	$5,000
80,000 BTU, 95%+ efficiency	$1,700	$4,450	$4,850	$5,900
100,000 BTU, 80% efficiency	$1,352	$3,900	$4,250	$5,450
100,000 BTU, 95%+ efficiency	$1,828	$4,550	$4,950	$5,950

Installation averages $3,142 nationally for the common size (DOE, inflated to August 2026); about 28% of that is labor, which we scale to local wages.

Extras that may be added

Item	Typical	Range
New vent connector	$375	$300–$488
Flue or chimney liner update	$1,133	$906–$1,473
Condensate pump	$200	$160–$320

What moves the price

80% versus 95% efficiency

A condensing furnace pulls more heat from the gas and sends cooler exhaust out through PVC. DOE's 2023 analysis assumes every condensing replacement needs new PVC flue venting and condensate removal, and most need combustion air piping too. Equipment for a 95% unit also costs more. In cold climates the gas savings usually make up the difference over time. In mild ones it takes longer.

The orphaned water heater problem

When a gas furnace that shared a chimney with a gas water heater is replaced by a condensing furnace vented through the wall, the water heater is left alone in a flue sized for both. DOE counts this in about 7% of condensing replacements. The fix is often a chimney liner or a vent change, which is why the flue liner extra appears on this page.

Heating capacity

Larger furnaces cost more, though not by much within one product line. The bigger risk is the wrong size. An installer who measures the house (a Manual J load calculation) may find the old furnace was oversized, which saves money on the new one. ENERGY STAR recommends sizing by calculation instead of copying the old nameplate.

Technician wages in your area

The labor share of DOE's average is adjusted by the 25th, median and 75th percentile pay for heating and air conditioning mechanics where you live, from the federal wage survey. Equipment prices do not change by region in this model.

Ductwork and accessories

Return air changes, a new filter cabinet, transitions to fit a different cabinet size, or a new thermostat all add cost. If the air conditioner coil sits on top of the furnace, the installer must reconnect it; a mismatched or leaking coil may lead to a recommendation to replace the AC at the same time.

Repair or replace?

Furnaces last a long time. DOE's analysis uses an average of about 21 years, with a range from 16 to 27. Failed igniters, flame sensors, pressure switches, inducer motors and control boards are all repairs to make on a furnace that is not near the end. A cracked heat exchanger is different. That is a safety problem, and the furnace gets replaced. Replacement also makes sense when a blower motor or board fails on a unit approaching 20 years, or when the last couple of years of repair bills add up to a real share of the range above. As for the efficiency standard, DOE's 2023 rule would require 95% AFUE for most gas furnaces made after December 18, 2028. As of mid-2026 the Supreme Court had sent the court challenge back for review, and DOE was weighing a petition to delay the date to at least 2030. Check the current status before letting it drive your timing.

Run the numbers for your unit.

What a complete quote lists

Brand, model number, BTU input and AFUE rating of the new furnace
How the size was chosen, ideally a written load calculation
Removal and disposal of the old furnace
Venting: new PVC intake and exhaust for a condensing unit, or vent connector work for an 80% unit
Chimney or water heater vent changes if the water heater will be orphaned
Condensate drain line, trap and pump if there is no floor drain
Gas connection, shutoff valve and sediment trap, plus a leak test
Plenum and duct transitions, filter rack, and reconnection of the AC coil if present
Permit, inspection and any required combustion safety test
Equipment warranty (parts and heat exchanger) and the contractor's labor warranty

Paste your quote and we'll tick these off for you.

Gas furnace prices by metro

Common questions

Should I pick an 80% or a 95% furnace?

In cold climates a 95% furnace usually pays back through lower gas bills. In mild climates, or where a condensing vent route is very difficult, an 80% furnace may cost less over its life. Ask for both prices if your installer can do either. ENERGY STAR's southern and northern labels reflect that the climate changes the math.

Is the 95% furnace rule in effect?

DOE adopted the rule in 2023 with a December 18, 2028 manufacturing date. In 2026 the Supreme Court vacated an appeals ruling that had upheld it and sent the case back, and DOE took comments on a petition to delay it to at least January 1, 2030. As of this writing the 2028 date had not been formally changed. Check for updates.

Why did my quote include a chimney liner?

Usually because a water heater will be left alone in a chimney once the furnace stops using it, or the existing flue is damaged or oversized. DOE's 2023 analysis includes flue updating, including relining, for a share of replacements. Ask the installer to explain which one applies.

How long does a gas furnace last?

DOE uses an average of about 21.4 years, with a low scenario of 16 and a high of 27. Home inspection charts give 15 to 25 years. Yearly filter changes and service help it reach the upper end.

Do I need to replace the AC at the same time?

Not always. If the air conditioner is fairly new and its indoor coil fits the new furnace, it can stay. If the AC is old, ENERGY STAR notes that pairing new equipment helps it reach its rated efficiency, and doing both at once saves a second round of labor.