How Much Does Furnace Replacement Cost?
By the HomeLintel Editorial Team · Reviewed 2026-08-24
A gas furnace replacement typically costs $3,800–$9,500 installed, with most homes around $6,000 for an 80,000–100,000 BTU unit. Electric furnaces ($2,500–$6,000) install cheaper but cost far more to run; oil furnaces and fuel conversions price higher and case-by-case.
The core buying decision is efficiency tier: a standard 80% AFUE furnace vents through existing metal flues, while a condensing 95–97% AFUE unit extracts more heat but requires PVC venting and condensate drainage — which is why the high-efficiency premium includes install work, not just equipment.
Cost breakdown: gas furnace swap
| Item | Typical range | Notes |
|---|---|---|
| Furnace (80% AFUE) | $1,600 – $3,200 | Single-stage workhorses; the mild-climate value pick. |
| Furnace (95–97% AFUE) | $2,500 – $4,800 | Condensing, two-stage/modulating options. |
| Labor | $1,200 – $3,000 | Removal, set, gas and flue connections, startup. |
| Venting changes (condensing) | $300 – $1,200 | PVC intake/exhaust runs and condensate drain. |
| Code items | $150 – $700 | Gas shutoff, drip leg, disconnect, smoke/CO placement rules. |
| Permit & inspection | $100 – $500 | Mechanical permit; inspection verifies venting and gas. |
80% vs 96%: the honest math
The efficiency premium — typically $1,200–$2,500 all-in — pays back through fuel saved, so climate decides. In cold-winter states burning 600+ therms a season, a 96% unit against an old 80% saves enough to pay back in 5–8 years. In mild-winter states the payback stretches past the furnace's life, and an 80% unit (or better, a heat pump) is the rational buy. One caveat: some cold-climate jurisdictions now require condensing efficiency at replacement — your installer will know.
The heat pump question belongs here too
If your AC is also aging, price a heat pump against furnace-plus-AC — one system replacing both, at similar combined cost, usually cheaper to run annually. If the AC is young and winters are serious, a straight furnace swap or a dual-fuel arrangement makes sense. Furnace-only replacement remains the right call more often in cold, cheap-gas states.
Replace-now triggers vs judgment calls
A cracked heat exchanger is the non-negotiable: it can leak combustion gases including carbon monoxide into supply air, and replacement — not repair — is the answer on any unit old enough to crack. Judgment territory: repeated igniter/board failures past year 15, rising fuel bills, and comfort complaints. Cheap fixes worth making at any age: igniters, flame sensors, capacitors, and blower motors on younger units.
Frequently asked questions
How much does a new furnace cost installed?
Gas: $3,800–$9,500, typically around $6,000. The spread is efficiency tier (80% vs 95%+ AFUE), venting changes for condensing units, and regional labor. Electric furnaces: $2,500–$6,000 installed.
How long does a furnace last?
Gas furnaces typically last 15–20 years; well-maintained units in mild climates stretch further. Electric furnaces often exceed 20 years. Past 15, plan replacement at the next major failure rather than being forced by a January breakdown.
Is a 96% furnace worth it over 80%?
In cold climates with real heating seasons, usually yes — 5–8 year payback plus comfort gains. In mild climates, usually no; the premium never returns. Local code may also mandate condensing units in some cold states.
Can a furnace and AC share the same blower?
Yes — in standard split systems the furnace's blower moves air for both heating and cooling, which is why furnace condition matters when replacing an AC and why matched, same-time replacement often makes sense on aging systems.
Related resources
Sources & methodology
- US DOE — Furnaces and Boilers — AFUE and replacement guidance
- US CPSC — Carbon Monoxide Safety — CO risk context for heat exchangers
Cost ranges are HomeLintel editorial estimates built from the listed sources and our published assumptions — they are not quotes. Last reviewed 2026-08-24. See how we estimate costs.