Furnace Replacement Cost (2026)
According to ContractorRanks editorial research, furnace replacement costs in the US run $3,800–$8,500 for an 80% AFUE single-stage gas unit and $5,500–$13,000 for a 96–98% AFUE modulating gas furnace. The breakdown below covers gas, oil, and electric; 80% through 98% AFUE; plus the line items that contractors often leave out of "we'll-handle-it" estimates (electrical, condensate, flue, permit, tax). Last reviewed June 8, 2026.
How ContractorRanks Researched Furnace Pricing
Furnace replacement is one of the most flat-bid HVAC jobs, which makes the pricing data unusually clean. ContractorRanks tracks this category using three sources:
- AHRI Directory — the Air-Conditioning, Heating & Refrigeration Institute's certified equipment database. Source of truth for unit specifications, AFUE ratings, and manufacturer-published MSRP.
- Installed flat-bid quotes contributed by HVAC contractors across the 11 tracked metros. Quotes are normalized by AFUE tier, BTU size, and fuel type. Gas vs oil vs electric breakdowns are kept separate because the labor and ancillary costs differ significantly.
- HVAC distributor pricing from dealer networks (Carrier/Bryant, Trane/American Standard, Lennox, Goodman/Daikin) and supply houses like Ferguson HVAC. Permit fees pulled directly from municipal building department schedules.
Pricing reflects installed-quote data as of June 8, 2026. AFUE tier is the largest single price driver — moving from 80% to 96% adds $1,500–$3,500 to most quotes, often recouped via utility rebates and lower operating cost over 5–7 years. See ContractorRanks methodology for the editorial standards.
Quick Answer
- 80% AFUE gas (100K BTU): $3,200–$5,200 installed
- 95% AFUE two-stage: $5,000–$7,200 (most common pick)
- 98% modulating: $6,400–$9,000
- Oil furnace replacement: $5,300–$9,000
- Electric: $2,400–$4,300 (cheapest install, highest run cost)
- Project timeline: 4-8 hours for like-for-like swap
Installed Cost by Furnace Type
| Type | Equipment | Labor | Total Installed | Notes |
|---|---|---|---|---|
| 80% AFUE single-stage gas (60K BTU) | $1,400 – $2,100 | $1,200 – $2,000 | $2,600 – $4,100 | Smaller home, mild climate |
| 80% AFUE single-stage gas (100K BTU) | $1,800 – $2,800 | $1,400 – $2,400 | $3,200 – $5,200 | Standard whole-house replacement |
| 95% AFUE two-stage variable-speed (60K BTU) | $2,400 – $3,400 | $1,600 – $2,600 | $4,000 – $6,000 | Sidewall PVC venting |
| 95% AFUE two-stage variable-speed (100K BTU) | $3,200 – $4,400 | $1,800 – $2,800 | $5,000 – $7,200 | Most common high-efficiency pick |
| 98% AFUE modulating variable-speed (100K BTU) | $4,400 – $5,800 | $2,000 – $3,200 | $6,400 – $9,000 | Carrier Infinity, Lennox SLP99V, Trane S9V2 |
| Oil furnace (100K BTU) | $2,800 – $4,500 | $2,500 – $4,500 | $5,300 – $9,000 | Includes new oil tank if needed |
| Electric furnace (15-20 kW) | $900 – $1,800 | $1,500 – $2,500 | $2,400 – $4,300 | Cheapest install, highest run cost |
Hidden Line Items That Show Up on the Final Invoice
PVC venting kit — $250 – $650
Required when switching from atmospheric (B-vent) to 90%+ AFUE. New 2" or 3" PVC out through the sidewall, plus condensate drain piping. Long runs (over 25 ft) push toward the upper end.
Condensate pump — $180 – $350
High-efficiency furnaces produce 1-2 gallons of acidic condensate per day. If the furnace sits below the floor drain, you need a pump. Most basement installs need this.
Gas line upsize — $350 – $1,200
Going from 60K to 100K BTU input might exceed the existing 1/2" gas line capacity. New 3/4" or 1" line plus a pressure test is mandatory under IFGC 406.
Electrical disconnect — $120 – $280
NEC 422.31 requires a service disconnect within sight of the furnace. Pre-1990 installs often don't have one and the inspector will require it added.
Smart thermostat — $180 – $450
Most quotes include a basic programmable thermostat. Spec a Nest, Ecobee, or Honeywell T9 if you want the comfort and remote control. The labor to wire it is the same.
Permit + inspection — $80 – $400
Mandatory in every jurisdiction. Skipping the permit voids most homeowner's insurance claims related to the furnace. The inspection is usually included in the permit fee.
Regional Cost Adjustments
| Region | Labor Adjustment | What's Driving It |
|---|---|---|
| San Francisco / Bay Area | +45 to +60% | High labor + permit fees |
| NYC / Long Island / NJ | +35 to +50% | Union labor common; access in old buildings |
| Boston / Eastern MA | +30 to +40% | Old housing stock; asbestos abatement common |
| Los Angeles / San Diego | +20 to +30% | Seismic strapping; permit costs |
| Seattle / Portland | +15 to +25% | High labor; tight permit reviews |
| Chicago / Cook County | +10 to +20% | Licensed contractor required |
| Denver / Boulder | +5 to +15% | High-altitude derating required |
| Atlanta / Charlotte / Nashville | Baseline | National reference |
| Dallas / Houston / Austin | -5 to +5% | Competitive independent market |
| Phoenix / Las Vegas | -5 to +5% | AC dominates; furnace work is shoulder season |
| Rural Midwest / Plains | -20 to -30% | Lower labor; gas conversions common |
| Rural Southeast | -15 to -25% | Lower labor; heat pump alternative |
"Most homeowners don't realize the AFUE rating is half the story. A 95% unit running with crushed return ducts and a clogged filter delivers about 78% actual efficiency. Spend the money on a Manual J, fix the duct restriction, then size the furnace. Skip those steps and you bought a Carrier Infinity and you're heating like it's a 1995 Janitrol."
— Bob Sarancik, 25-year HVAC contractor, Pittsburgh PA
Related
Frequently Asked Questions
How does ContractorRanks calculate furnace replacement costs?
ContractorRanks tracks furnace installation pricing across 11 US metros using AHRI Directory equipment data, HVAC contractor flat-rate quotes (furnace replacement is almost always a flat-bid job), and supplier pricing from major distribution networks (Carrier/Bryant, Trane/American Standard, Lennox, Goodman/Daikin). Prices include the unit, installation labor, basic flue/venting work, condensate handling for high-efficiency models, and city permit. AFUE tier (80% / 96% / 98% modulating) is the largest single price driver.
Where does ContractorRanks source furnace pricing data?
Three sources: (1) AHRI (Air-Conditioning, Heating & Refrigeration Institute) Directory for certified unit specifications and manufacturer-published MSRP, (2) installed flat-bid quotes contributed by HVAC contractors in the 11 tracked metros — furnace replacement is one of the most flat-bid jobs in the trades, so quote data is consistent, and (3) HVAC distributor price sheets through dealer networks (Ferguson HVAC, Carrier dealer programs, Goodman supply). Permit fees are pulled directly from municipal building department schedules.
Should I replace a 15-year-old furnace that still works?
Depends on three numbers — efficiency rating, repair history, and your gas bill. An 80% AFUE furnace from 2010 is wasting 20¢ of every dollar of gas vs a modern 95% unit. In a cold-climate zone (Minnesota, upstate NY, MT) that's $400-$700/yr in extra fuel. If the heat exchanger is original and you've had two service calls in three years, the cracked exchanger conversation is coming. We've watched too many homeowners try to nurse an old furnace through one more winter and end up with a no-heat call on Christmas Eve at emergency rates. If the unit is past 18 years, replacement isn't optional in three years anyway. Replace on your timeline, not the breakdown's.
What's the real cost difference between 80% and 95% AFUE?
For the same BTU size: 80% single-stage runs $1,800-$3,000 equipment, 95% two-stage modulating runs $3,200-$4,800 equipment. Installation labor is similar (~$1,400-$2,400) but 95% needs PVC venting through a sidewall instead of B-vent through the roof, which can save or add $300-$600 depending on existing flue path. The annual fuel savings on a 100K BTU unit in Climate Zone 5: about $280-$420/yr at current natural gas prices. Simple payback: 4-7 years on the efficiency upgrade. After that it's pure savings until year 18-22 when the unit reaches end of life.
Is a modulating furnace worth the premium over two-stage?
Modulating furnaces (Carrier Infinity 98, Lennox SLP99V, Trane S9V2) ramp output from about 35% to 100% in small increments. Two-stage runs at 65% or 100%. The comfort difference is real — modulating units hold room temperature within ±0.5°F vs ±2°F for two-stage. In a tightly built modern home, modulating prevents the "blast of hot air then long cold gap" cycle that two-stage produces. The premium is $1,200-$2,200 over two-stage. Worth it in tight new construction (2018+ IECC homes). Not worth it in a drafty 1970s ranch where the envelope leaks faster than the furnace can hold setpoint anyway.
How is the right furnace size determined?
Properly: a Manual J load calculation (we have a free screening calculator at /hvac-load-calculator). Practically: most contractors just match the existing nameplate. The problem is the existing nameplate is usually wrong because the original installer also matched the previous nameplate going back to 1985 when the house had R-7 walls and single-pane windows. A modern home with R-19 walls and double-pane low-e windows needs 30-50% less furnace than the rule-of-thumb suggests. We've seen 100K BTU units quoted for homes that genuinely need 60K. Oversizing a furnace causes short cycles, uneven heat distribution, and faster heat exchanger fatigue. Ask for the Manual J in writing before signing the install contract.
What's a fair installed price for a 100K BTU 95% AFUE furnace?
Atlanta metro reference price for a 100K BTU input 95% AFUE two-stage variable-speed furnace (Carrier 59TN6, Trane S9X2, Lennox EL296V): $5,800-$7,500 installed by a reputable independent contractor. National franchises (One Hour Heating, ARS Rescue Rooter) typically quote 25-40% higher for the same equipment. Regional adjustments: SF Bay/NYC +45-60%, rural Midwest -20 to -30%. The quotes that come in under $4,500 usually substitute a single-stage 95% which is fine equipment but not what most quotes describe. Read the model number on the proposal — that's where the truth lives.
How does the federal heat pump tax credit affect this decision?
Under the Inflation Reduction Act, qualifying heat pumps get a 30% federal tax credit capped at $2,000/year. Gas furnaces don't qualify. In milder climates (Zones 3-4), replacing a gas furnace with a cold-climate heat pump (Mitsubishi Hyper-Heat, Carrier Greenspeed) is increasingly competitive: $14,000-$19,000 installed minus $2,000 federal credit minus typical state/utility rebates ($800-$3,500 depending on state) = net $8,500-$14,500 — comparable to a high-end modulating gas furnace install. The math fails in Zones 6-7 where temperatures regularly hit -10°F and even cold-climate heat pumps need substantial backup heat strips.