Great Falls, MT Furnace Replacement Cost (2026): $4,100

Refine your estimate

Tune it to your home to narrow the furnace replacement range.

Home size2,000 sq ft

800 sq ft4,500 sq ft

Quality tier

Conditions & add-ons

Your adjusted estimate

$4,100 – $7,350

Most likely $5,750

Key takeaways for Great Falls

Expect $4,100 to $7,350 for furnace replacement in Great Falls; most quotes cluster near $5,750, about 6% above the national average.
Local labor in Great Falls is −9% relative to the national average, which is what pushes this estimate away from the countrywide number.
The estimate already covers the HVAC permit — roughly $200 in Great Falls.
Schedule the replacement early — this typically holds up 15–30 years, and an emergency swap costs full price.
Roughly 5–15% comes off when you book in Spring and fall (Mar–May, Sep–Oct) instead of peak season.
Check the rebates section below before you commit — 25C/25D federal credits and utility incentives can cut the net cost.

Price breakdown

What goes into the price in Great Falls

A typical Great Falls furnace replacement of $5,750 breaks down roughly like this — materials priced near the national level, labor set by local rates.

Line item	Great Falls 2026 range
Materials & equipmentThe unit and materials — largely the same cost no matter which city you're in.	$1,550 – $2,850
Labor & installationThe installation work itself — removal, setup and startup — is what your city's labor rate actually moves.	$2,350 – $4,300
Permit & feesWhat this city's building department charges for a HVAC permit.	$200
Total installed cost	$4,100 – $7,350

Split from the Great Falls estimate using a 60% local-labor share; line items sum to the total.

Local factors

Why furnace replacement costs what it does in Great Falls

Great Falls's labor rates sit about 9% lower than the national average (based on price levels for the Great Falls metro area), pushing the price down.
Great Falls's cold climate increases typical furnace replacement cost by about 8% versus a neutral climate.
Great Falls's HVAC permit runs roughly $200, which is already part of the number above.

Winters here are genuinely cold, which means backup or dual-fuel capacity, not the headline rating, decides how furnace replacement holds up on the worst mornings. Prioritise a high-efficiency, properly-sized unit that can hold temperature through sustained sub-freezing spells, and confirm insulation and sealing first.

By size

Furnace Replacement cost by home size in Great Falls

Furnace cost scales with the heating capacity (BTU) your home needs — roughly 40–45 BTU per square foot in a mixed climate. Larger homes need a bigger unit and more ductwork.

home size	Great Falls 2026 range
1,000 sq ft (≈45,000 BTU)	$3,050 – $5,500
1,500 sq ft (≈68,000 BTU)	$3,550 – $6,350
2,000 sq ft (≈90,000 BTU)	$4,100 – $7,350
2,500 sq ft (≈110,000 BTU)	$4,700 – $8,350
3,000 sq ft (≈130,000 BTU)	$5,300 – $9,400
3,500+ sq ft (≈150,000 BTU)	$5,900 – $10,400

National size ranges localized to Great Falls labor and climate.

By type

Furnace Replacement cost by type in Great Falls

Gas furnace	$4,000 – $7,300
High-efficiency gas furnace	$3,600 – $7,300
Electric furnace	$2,250 – $4,800

Adjusted to Great Falls from national type-level ranges.

By efficiency

Furnace Replacement cost by efficiency in Great Falls

Efficiency is measured in AFUE — the percentage of fuel turned into heat. Higher AFUE costs more upfront but cuts fuel bills, and in cold (northern) regions the DOE requires ≥95% AFUE gas furnaces.

80% AFUE (standard)Lowest upfront; fine in mild climates	$3,250 – $5,800
90–95% AFUE (high-efficiency)Best all-round value in most regions	$4,100 – $7,350
96%+ AFUE (condensing, premium)Lowest fuel bills; required in cold zones	$5,300 – $9,900

Where the money goes

Labor vs. materials in Great Falls

Labor (60%)

≈ $3,450

Install crew, removal, permit & startup — the part Great Falls rates move most.

Materials (40%)

≈ $2,300

Equipment & materials — priced closer to the national level.

Split based on a typical $5,750 Great Falls project; your mix varies with scope.

Methodology

How we estimate it

National range	$3,800 – $7,000
Great Falls labor adjustment	×0.95
cold climate factor	×1.08
Local permit	+$200
Great Falls estimate	$4,100 – $7,350

Typical 2026

$5,750

Range

$4,100 – $7,350

Climate

cold

Local permit

$200

Promo prices vs. the real cost

That eye-catching install price in the ad is bait for a service visit, not the cost of a finished system — set it beside the real installed estimate above:

"Free" replacement estimate$0 — it's a sales visit
Seasonal tune-up promo$79–$129
Service call / diagnostic fee$75–$150
Financing offers$0 down · 0% APR, 12–60 mo

Hidden costs

Additional furnace replacement costs to budget for

Treat them as possibilities, not certainties — the ones that reach your quote follow your property's age and setup.

Old furnace removal & disposal	$50 – $330
New ductwork (vs. repair $300–$1,500)Only if ducts are missing or failing	$1,000 – $5,000
Gas line run or upgrade	$250 – $800
Chimney liner (for high-efficiency venting)	$600 – $2,500
Smart thermostat	$150 – $500

Typical national add-on ranges; confirm locally during your quote.

What's included

Installation labor and basic ductwork connections
Removal and disposal of the old unit
The furnace unit and burner assembly
Thermostat connection and system startup/testing

What affects the cost

Whether a chimney liner or new gas line is required
Heating capacity (BTU) needed for your square footage
Fuel type (gas vs electric) and AFUE efficiency rating
Condition of existing ductwork and venting

Ways to save on furnace replacement in Great Falls

Look for utility rebates on high-efficiency models
Schedule in the off-season (spring/summer) for better rates
Get at least 3 quotes — installed prices vary widely
Right-size the unit; oversizing wastes money and cycles hard

Lifespan

How long does furnace replacement last in Great Falls?

Expected lifespan

15–30 years

Gas furnaces typically last 15–20 years; well-maintained units can reach 30.

Annual maintenance

$70–$300/yr

An annual tune-up keeps efficiency up and protects the warranty.

When to replace

Signs you need furnace replacement in Great Falls

The furnace is 15+ years old (near or past its service life)
Heating bills keep climbing despite no change in usage
Some rooms are warm while others stay cold (uneven heating)
Frequent repairs — you've called for service more than once or twice recently
Banging, rattling or screeching noises on startup
A yellow or flickering burner flame instead of steady blue (have it checked immediately)
More dust, dryness, or a stale smell when the heat runs

Decision

Repair or replace in Great Falls?

The $5,000 rule: multiply the repair quote by the furnace's age in years. If it tops $5,000, replacement is usually the smarter spend.

Repair if…

The unit is under ~10 years old and otherwise efficient
The fix is a single inexpensive part (igniter, flame sensor, capacitor)
It's still under manufacturer warranty

Replace if…

It's 15+ years old and needs a major part
The heat exchanger is cracked (a safety issue — replace, don't repair)
The repair costs more than about half of a new system
It's an 80% AFUE unit and your fuel bills are high in a cold climate

Rebates & incentives in Montana

Most 2026 rebates reward switching to a heat pump, not a like-for-like gas furnace. Replacing a gas furnace, your savings are mainly utility efficiency rebates (high-AFUE models) — but pricing out a heat pump often qualifies you for far larger rebates.

The federal 25C tax credit (up to $2,000 for heat pumps; $600 for high-efficiency AC or furnaces) and the 25D credit ended December 31, 2025 under the One Big Beautiful Bill Act — neither is available for 2026 installs. The remaining federal help is the IRA Home Electrification & Appliance Rebates (HEAR): up to $8,000 toward a heat pump for households under 150% of area median income, paid at point of sale where a state has launched its program.

Verified July 2026. Rebate budgets deplete and program windows change fast — confirm current amounts and eligibility with your utility and the DSIRE database before you budget. Costadia does not administer these programs.

Best time to buy

Cheapest time for furnace replacement in Great Falls

Crews are busiest — and priciest — exactly when it's hottest or coldest, since that's when systems fail under load. Book in the mild months and you're negotiating from a position of choice, not a broken furnace.

Best window

Spring and fall (Mar–May, Sep–Oct)

Avoid

Peak summer and mid-winter

Off-peak savings

5–15%

Don't wait for a breakdown — book AC replacement in the cooler months and furnace work in the warmer ones, so you're comparing quotes instead of taking whoever answers the phone.

Reading your quotes

Why furnace replacement quotes vary — and how to compare them fairly

When two quotes for one project diverge by thousands, the cause is usually what each one includes, not markup — here's how to read the difference.

Why a quote looks high (or low)

Equipment tier isn't matched — a 14.3 SEER2 bid will always undercut an 18 SEER2 one for the "same" job.
One quote bundles ductwork, electrical, permit and old-unit removal; another quietly leaves them out.
Sizing was guessed from square footage instead of a Manual J load calculation, so the equipment is wrong.

Get an apples-to-apples bid

Get at least three written bids before you sign.
Insist on a Manual J load calculation, not a square-footage guess.
Require an itemized quote splitting equipment, labor, permit and add-ons.
Ask every bidder for the same SEER2/AFUE rating so you compare like for like.

Hiring

Questions to ask Great Falls HVAC pros

The only honest way to compare is to hold every quote to one checklist. Start with these.

1Did you run a Manual J load calculation to size the system, or estimate from square footage?
2What AFUE/SEER2 rating is this unit, and what's the payback vs. the next tier up?
3Is removal of the old equipment, the permit, and startup testing included in the quote?
4Will my existing ductwork and venting work as-is, or is repair/resizing needed?
5What's covered under the labor warranty vs. the manufacturer's parts warranty?

FAQ

Furnace Replacement in Great Falls

How much does furnace replacement cost in Great Falls, MT?

Most Great Falls homeowners pay around $5,750 for furnace replacement, though 2026 quotes stretch from $4,100 to $7,350. Strip out Great Falls's labor rates, its cold climate and permit fees and you'd be left with a national average — this range keeps them in.

Is furnace replacement more expensive in Great Falls than average?

Labor is the biggest lever here: at an index of 0.95 versus the US average, Great Falls ends up about 6% higher than the national average., plus a local HVAC permit running about $200.

Do I need a permit for furnace replacement in Great Falls?

The estimate above already covers the HVAC permit Great Falls generally requires for this job, so the $200 or so it costs won't land as a surprise.

What affects furnace replacement cost the most?

Replacing a residential furnace, including the unit and installation labor. Your cold climate zone plays a part, but equipment/material grade, the size and complexity of the home, and local labor rates weigh in just as heavily.

Editors' roundtable

How much should you really budget for HVAC in 2026?

Get the sizing wrong or the efficiency tier mismatched to your climate, and the price drifts fast in either direction. Below, a look at how those choices — plus brand markup — shape the real number.

The efficiency-first case

High runtime changes the math. In a demanding climate the extra efficiency of a heat pump or a top-tier SEER2/AFUE unit gets paid back month after month on the utility bill, and state and utility incentives can shave the upfront figure further now that the federal 25C/25D credits have expired. Price the lifetime bills, not just the tag, before you default down.

The budget-first case

Size the system to your home with a Manual J calculation and buy the standard efficiency tier (80% AFUE / 14.3 SEER2). In a mild climate the cheaper unit pays off because you rarely run it hard — paying for premium efficiency you won't use is the most common way to overspend.

The longevity case

Brand is a footnote; sizing and install quality write the story. A right-sized mid-tier system that's properly commissioned and serviced once a year will outlive an oversized premium unit that short-cycles itself to an early grave. Put the money into the crew and the setup rather than the nameplate.

Our take

Get the sizing and the commissioning right and the brand debate mostly disappears. Insist on a Manual J, pick an efficiency tier your climate can justify, and pocket every incentive that still applies after the federal credits lapsed.

Editorial analysis by Serhat Özçelik, reviewed by Costadia Editorial. These are our own cost perspectives, not third-party endorsements.

How we calculated this estimate

We start with 2026 national furnace replacement ranges compiled from contractor-pricing sources (Angi, HomeGuide, Fixr and EnergySage averages), then localize them to Great Falls using the BEA Regional Price Parity labor index (×0.95 here), the IECC cold-climate factor (×1.08) and a typical local permit fee (≈$200). Federal incentive details reference the IRS Inflation Reduction Act (25C/25D) and DSIRE.

This is a planning estimate, not a quote.Actual prices vary with your home's condition, equipment grade and contractor — always confirm with licensed local pros before budgeting.

By Serhat ÖzçelikReviewed by Costadia EditorialUpdated June 2026Sources: BLS · BEA · IECC · IRS · DSIRE · industry cost data

References & data sources

Our Great Falls furnace replacement estimate is built from these primary, mostly government sources — not a single aggregator.

Occupational Employment & Wage Statistics (metro wages) — U.S. Bureau of Labor Statistics.Metro-level trade wages behind each city's labor index.
Regional Price Parities (state & metro) — U.S. Bureau of Economic Analysis.Regional price levels used where metro wage data is unavailable.
IECC Climate Zones — U.S. DOE — Building Energy Codes Program.Climate-zone factors applied to weather-sensitive projects.
Home Energy Tax Credits (25C / 25D) — Internal Revenue Service.Federal rebate and tax-credit figures for eligible upgrades.
Database of State Incentives for Renewables & Efficiency — DSIRE — NC State University.State and utility incentive programs by ZIP code.