Replacing a furnace in 2026 commonly costs about $2,800 to $6,900 for a professionally installed system, with a national average near $4,800. Larger homes, high-efficiency equipment, fuel changes, venting work, duct modifications, and difficult installations can push the price well above that range.
Angi reports a 2026 national average of $4,814, with most projects between $2,823 and $6,896. HomeGuide places many standard-efficiency replacements around $3,500 to $7,500+, with high-efficiency installations reaching roughly $11,500 in some cases.
| Furnace project | Typical 2026 planning range |
|---|---|
| Typical installed furnace | $2,800–$6,900 |
| Standard-efficiency replacement | $3,500–$7,500+ |
| High-efficiency furnace | Up to about $11,500 |
| Gas furnace | $3,800–$10,000 |
| Electric furnace | $2,000–$7,000 |
| Oil furnace | $6,750–$10,000 |
| Propane furnace | $3,700–$14,200 |
What affects furnace replacement cost?
The biggest price drivers are furnace size, fuel type, efficiency, labor, venting, electrical work, permits, and whether the existing duct system can be reused. Replacing a furnace with a similar model in an accessible location is usually less expensive than changing fuel types or installing new venting and ducts.
Furnace cost by fuel type
Fuel type can change both the equipment cost and the installation scope. Angi’s current 2026 ranges place electric furnaces around $2,000 to $7,000 installed, natural gas around $3,800 to $10,000, oil around $6,750 to $10,000, and propane around $3,700 to $14,200.
Do not compare only equipment prices. A fuel conversion may require a new gas line, electrical circuit, venting, tank work, chimney changes, or other modifications that can materially change the project total.
How furnace size affects price
Furnaces are sized by heating output, commonly expressed in BTUs per hour. Larger-capacity equipment generally costs more, but a bigger furnace is not automatically better. Oversized equipment can cycle too frequently, reduce comfort, and waste energy.
ACCA identifies Manual J as the national ANSI-recognized residential load-calculation standard. A replacement should be selected from the home’s actual heating load, not simply by copying the capacity of the old furnace.
What does AFUE mean?
AFUE stands for Annual Fuel Utilization Efficiency. DOE defines it as the percentage of annual fuel energy that becomes useful heat delivered to the home. A 95% AFUE furnace converts a greater share of its fuel into useful heat than an 80% AFUE model.
Higher efficiency can reduce fuel use, but the best financial choice depends on climate, fuel prices, how long you expect to own the home, and the installed-price premium. DOE’s purchasing guidance illustrates that the value of higher AFUE varies by region and heating demand.
Do you need new ductwork?
Not necessarily. If the existing ducts are correctly sized, reasonably tight, and in good condition, they may be reused. But damaged, undersized, poorly designed, or leaky ducts can undermine a new furnace. Ask the contractor whether the quote includes duct inspection, sealing, transitions, return-air changes, or replacement.
Repair or replace the furnace?
A furnace repair can make sense when the system is relatively young, the heat exchanger and major components are sound, and the repair is modest. Replacement becomes more attractive when the furnace is older, needs repeated repairs, has a serious safety problem, or the repair cost is a large percentage of replacement cost.
Angi’s 2026 repair-versus-replace guidance uses about 15 years as a practical age checkpoint and notes that very large repairs can tilt the decision toward replacement. Safety problems involving carbon monoxide, combustion, or a damaged heat exchanger should be evaluated by a qualified HVAC professional.
Should you replace the furnace and AC together?
Sometimes. If both systems are old, replacing them together can reduce duplicated labor and make it easier to install matched equipment. Angi currently places combined furnace-and-AC replacement around $5,000 to $12,500 for many projects.
If the air conditioner is newer and working well, replacing only the furnace may be reasonable. Compare the cost of furnace-only replacement with the cost of replacing both systems and ask whether keeping the existing cooling equipment creates compatibility or warranty issues.
What should a furnace replacement quote include?
- Manufacturer and exact model number
- Heating capacity and the load calculation used to size it
- AFUE efficiency rating
- Thermostat and controls
- Ductwork changes and sheet-metal transitions
- Gas, electrical, condensate, and venting work
- Permit and inspection fees
- Removal and disposal of the old furnace
- Manufacturer and labor warranties
- Total installed price and optional upgrades
Questions to ask before you buy
- Can you show me the Manual J load calculation?
- Why is this furnace capacity appropriate for my house?
- What AFUE am I buying, and what does the higher-efficiency option cost?
- Does the quote include permits, removal, venting, and duct modifications?
- What labor warranty do you provide?
- Would replacing my air conditioner at the same time materially reduce total labor or improve compatibility?
Furnace replacement cost: bottom line
For 2026 budgeting, many homeowners can start with roughly $2,800 to $6,900 for a furnace replacement, while high-efficiency, fuel-conversion, large-capacity, or difficult installations can cost substantially more. The strongest quote is not simply the lowest number; it is the one that clearly explains equipment size, efficiency, installation scope, safety work, permits, warranties, and the total installed price.
For the broader system picture, see RefitZen’s HVAC replacement cost guide and HVAC installation cost guide.
Frequently asked questions
How much does a new furnace cost in 2026?
Angi reports a 2026 national average near $4,814, with many professionally installed projects between $2,823 and $6,896.
How much is a high-efficiency furnace?
High-efficiency installations can cost materially more than standard equipment. HomeGuide reports some high-efficiency furnace projects reaching roughly $11,500 installed.
Should I replace a 20-year-old furnace?
Age alone does not decide the question, but a 20-year-old furnace with frequent repairs, declining reliability, safety concerns, or high operating costs is a strong candidate for replacement evaluation.
Is a larger furnace better?
No. The furnace should be sized to the home’s heating load. ACCA Manual J is the recognized residential load-calculation method used to determine that requirement.
More RefitZen Cost Guides
Related guides: HVAC Replacement Cost, Heat Pump Replacement Cost, and HVAC Installation Cost. Browse the full RefitZen Costs library.
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