HVAC Replacement Cost in Helena, MT (2026)
Updated October 2026 · Helena, MT · index 0.98
How much does a new HVAC system cost in Helena? For a 3-ton system with central AC + gas furnace, homeowners in Helena, MT pay about $10,300 on average, and most quotes land between $7,050 and $13,600 — $2,342 to $4,522 per ton. The price covers removing the old system, the new outdoor and indoor equipment, a new line set, electrical and condensate connections, the thermostat, the permit, start-up and commissioning.
The HVAC replacement price in Helena runs 2% below the U.S. average: construction labor in the Helena area runs 3% below the national mean, materials sit at the national level. The same job averages $10,500 nationally and about $10,300 at the Montana statewide index.
HVAC Replacement cost calculator for Helena
1.5 to 5 ton
Are you a HVAC contractor? Price jobs like this in 60 seconds
HVAC replacement price in Helena by system type
What a 3-ton system costs in Helena with each system type, installed:
| Option | Average · range |
|---|---|
| Central AC + gas furnacesplit AC, matched coil and an 80,000 BTU furnace$3,432 per ton | $10,300$7,050 – $13,600 |
| Heat pump + air handlerall-electric split heat pump, no furnace$3,183 per ton | $9,550$6,400 – $12,700 |
| Cold-climate heat pump + air handlervariable-speed heat pump rated for deep winter$3,636 per ton | $10,900$7,350 – $14,500 |
The least expensive option in Helena is heat pump + air handler, at about $9,550; cold-climate heat pump + air handler averages $10,900, 1.1 times as much.
Cost to replace an HVAC system in Helena by size
With central AC + gas furnace, priced for Helena, MT:
| Size | Average · range |
|---|---|
| A 2-ton system$4,468 per ton | $8,950$6,100 – $11,800 |
| A 3-ton system$3,432 per ton | $10,300$7,050 – $13,600 |
| A 4-ton system$2,914 per ton | $11,700$7,950 – $15,400 |
Some costs stay the same whatever the size — load calculation and equipment sizing, mechanical permit and inspection, old system removed, refrigerant recovered — so a bigger job costs less per unit: $2,914 per ton for a 4-ton system against $4,468 for a 2-ton system.
What an HVAC replacement in Helena includes
Line by line, the $10,300 average for a 3-ton system breaks down like this: 32% labor, 65% materials and equipment, and $280 in permit fees passed through at cost.
| Line | Low – high |
|---|---|
| Load calculation and equipment sizing | $70 – $220 |
| Mechanical permit and inspection | $150 – $400 |
| Old system removed, refrigerant recovered | $340 – $600 |
| Gas furnace (about 80,000 BTU) | $1,500 – $2,700 |
| Outdoor unit, set on a new pad | $2,250 – $4,200 |
| Matched indoor coil | $970 – $2,100 |
| New refrigerant line set (25 ft) | $370 – $600 |
| Disconnect, whip and thermostat wire | $210 – $340 |
| Condensate drain and safety switch | $110 – $260 |
| Gas connection and furnace venting | $310 – $580 |
| Plenums and transitions to the ducts | $260 – $600 |
| Programmable or smart thermostat | $220 – $410 |
| Evacuation and refrigerant charge | $110 – $220 |
| Start-up and commissioning | $110 – $260 |
| Warranty registration and walk-through | $60 – $130 |
Each line is the price book's U.S. rate for that step, scaled by 0.76 to the installed price published sources give for the whole job (see how these prices are built), times Helena's index of 0.98; permit fees are not scaled.
Get free quotes from Helena contractors
Describe your project once and JobFlex sends it to a local HVAC contractor who prices it for your home — free, no account needed.
What affects HVAC replacement prices in Helena
Labor and materials in Helena
Construction wages in the Helena area run 3% below the U.S. mean (BLS, May 2025), and materials in its ZIP codes price right at the national average. Together they give Helena a construction cost index of 0.98.
Where Helena sits in Montana
Helena is the 3rd most expensive of the 5 Montana cities in our index, against a statewide index of 0.98. Bozeman is the dearest at 1.03; Great Falls is the least expensive at 0.97.
Against the rest of the country
Of the 306 U.S. cities in JobFlex's index, Helena ranks 175th from the most expensive. The job that averages $10,300 here averages $10,500 at the national rate.
Climate a system is sized for in Montana
Contractors size equipment for the local design temperatures. Across Montana's counties the median is about 90°F on a hot summer day and -10°F on a cold winter night (ENERGY STAR county table), and your county can differ. Winters that cold are where a cold-climate heat pump or a furnace earns its price.
Sales tax in Montana
Montana has no state sales tax. Prices on this page are before any tax.
What a Helena contractor will ask before quoting
- Job type — new construction, replacement or upgrade — and the evidence for it
- Heating and cooling load for this house (not the old nameplate), tonnage, fuel and refrigerant
- Ducts, line set, circuit, gas line and flue: keep, fix or replace, each with its reason
- Water heater in scope, and whether it shared the old flue
- Panel main amps, free slots and the new equipment's MCA
- Permits, tests and incentives that apply in this state
HVAC replacement cost in other Montana cities
A 3-ton system with central AC + gas furnace averages $10,300 in Helena; $10,200 in Great Falls, $10,800 in Bozeman, $10,300 in Missoula.
| City | Average · range |
|---|---|
| Great Falls, MT1% less | $10,200$6,950 – $13,400 |
| Bozeman, MT5% more | $10,800$7,400 – $14,200 |
| Missoula, MTsame as Helena | $10,300$7,050 – $13,600 |
| Billings, MT2% more | $10,500$7,150 – $13,800 |
HVAC replacement price in Helena: questions
How much does a new HVAC system cost in Helena, MT?
About $10,300 for a 3-ton system with central AC + gas furnace, and most Helena quotes fall between $7,050 and $13,600. That is 2% below the U.S. average, where the same job averages $10,500.
What is the HVAC price per ton in Helena?
$2,342 to $4,522 per ton, about $3,432 on average with central AC + gas furnace. Smaller jobs cost more per unit, because the fixed costs are spread over less.
How much is a 4-ton system in Helena?
$7,950 to $15,400, about $11,700 on average, with central AC + gas furnace — $2,914 per ton.
Do you need a permit for HVAC replacement in Helena?
Yes — installing HVAC or fuel-burning equipment needs a permit nearly everywhere, Helena included. The prices on this page carry $150–$400 for the permit and inspection.
Does the price include sales tax in Montana?
No tax is included, and Montana has no state sales tax.
What size HVAC system does a house in Helena need?
It is worked out with a Manual J load calculation for the house — included in the prices above — not from square footage alone. Here it is run against design temperatures of about 90°F in summer and -10°F in winter (the Montana median).
Other home projects in Helena
HVAC replacement cost in Montana
How these prices are built
Every price on this page comes from JobFlex's contractor price book: what a homeowner pays a licensed contractor for each step of the job, as a U.S. national average per unit, with the contractor's overhead and profit included and sales tax left out. The HVAC replacement is priced step by step, then multiplied by Helena's construction cost index of 0.98.
Where the price book's steps for an option add up to more than 20% over the installed price a published source gives for the whole job, every step but a permit fee is scaled down to the middle of that range: central AC + gas furnace × 0.76 (HomeCostCalcs 2026: $7,000–$14,000); heat pump + air handler × 0.76, following central AC + gas furnace; cold-climate heat pump + air handler × 0.76, following central AC + gas furnace.
The index weighs local construction wages (BLS Occupational Employment and Wage Statistics, May 2025) at 60% and the area's material prices (Craftsman ZIP-area factors) at 40%. Published indices for Helena, each on its own base: HUD 0.94, Craftsman 0.95. Treat any city figure as about ±5%; a contractor's quote for your house is the number to plan with.
Contractors in Helena build quotes like these with JobFlex's HVAC estimator.
- HomeCostCalcs 2026: furnace + AC replacement $7,000-$14,000 standard, $10,000-$20,000 high efficiency
- Today's Homeowner 2025: complete HVAC system install $5,000-$12,500