How Much Does It Cost to Replace a Furnace?
Use $4,500–$10,500 as a HomeScore planning range for an installed 80k–100k BTU gas furnace, with $6,800 as the midpoint. This is a planning method, not a database of contractor invoices: local labor, fuel, sizing, access and code work still require written quotes.
Quick price points (2026)
| Scope | Cost | What it includes |
|---|---|---|
| Standard-efficiency swap | $4,500 | Like-for-like gas-furnace replacement where compliant venting, gas supply and the duct connection can be reused. |
| Typical high-efficiency install | $6,800 | Higher-AFUE gas furnace with ordinary venting or condensate changes, standard controls, startup and inspection. |
| Complex or premium install | $10,500 | Variable or modulating equipment, difficult access, or material venting, gas-line, electrical or control changes. |
What changes the quote?
- Equipment and efficiency tier
- Compare the exact make, model, BTU input/output and AFUE. AFUE is a seasonal fuel-use efficiency measure; it does not by itself predict one home's utility savings.
- Labor and standard materials
- Ask for equipment and labor/materials on separate lines so bids can be normalized.
- Venting and condensate
- Changing furnace type or efficiency may require a new vent path, condensate drain or pump.
- Gas, electrical, controls and duct transitions
- These are common scope differences. Require every bidder to state what is included and excluded.
- Permit, inspection and contingency
- Name who pulls the permit and schedules final inspection. Hold a 10–15% homeowner contingency outside the signed base bid for documented hidden conditions.
Make structural bids comparable
- Make, model, BTU and AFUE: Confirms the bids are pricing comparable equipment and a right-sized scope.
- Equipment separated from labor and materials: Makes the quote usable when one bidder bundles everything into a single number.
- Venting, condensate, gas, electrical, thermostat and duct changes: Prevents the most common scope differences from appearing as surprise change orders.
- Permit, inspection, disposal and startup: States who owns code compliance and commissioning.
- Exclusions and contingency: Keep a 10–15% homeowner reserve outside the signed base bid; release it only for documented added scope.
Sources & methodology
The $4,500–$10,500 figures are HomeScore planning values for an 80k–100k BTU gas furnace, not observed contractor-quote statistics or a national invoice average. They include professional labor, standard materials, startup and a permit/inspection allowance. Major ductwork, fuel conversion, asbestos or mold remediation and structural work are excluded. ENERGY STAR and DOE sources support the AFUE definition and efficiency comparison, not the dollar range.
Frequently asked
What does the furnace planning range include?
Equipment, professional installation, standard materials, startup and a permit/inspection allowance for an 80k–100k BTU gas furnace. Major ductwork, fuel conversion and remediation are outside the range.
Is $6,800 a national average from contractor invoices?
No. It is HomeScore's midpoint planning value. Use written local quotes for a property-specific budget.
What should every furnace quote separate?
The equipment model and AFUE; labor and standard materials; venting and condensate work; gas, electrical, controls and duct changes; permit, inspection, disposal and startup; and explicit exclusions.
How to budget for this project
- Get 3 quotes
Get itemized quotes from at least three licensed contractors in your area.
- Adjust for your region
Compare the same scope and account for regional labor and permitting.
- Add 10–15% contingency
Hidden conditions, code upgrades and permit fees can increase the original quote.
- Plan the cash, not the financing
Build the replacement cost into the home's repair plan before the work becomes an emergency.