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A new furnace cost in Billings usually lands in the same range national cost guides report, roughly $3,500 to $7,500 installed for most gas furnaces, with high-efficiency and larger systems costing more. Your final price depends on furnace size, efficiency (AFUE), ductwork and venting changes, and permits.
Pricing a new furnace in Montana is different from pricing one in a mild climate. Our winters push equipment hard, so sizing and efficiency matter more here than almost anywhere. This guide breaks the new furnace cost into each piece so you can read a quote with confidence. If you already know you need a replacement, our furnace installation team can give you a written quote after an in-home look.
Key Takeaways
- The new furnace cost for most homeowners is about $3,500 to $7,500 installed, based on national 2026 cost guides.
- Equipment is usually less than half the new furnace cost. Labor, venting, and duct work make up the rest.
- High-efficiency furnaces (90% AFUE and up) cost more upfront but use less gas through a long Billings heating season.
- Correct sizing through a load calculation protects comfort and keeps the system from short cycling.
- A written, itemized quote is the best way to compare contractors fairly.
What Does a New Furnace Cost in Billings in 2026?
The new furnace cost for a typical Billings home starts with the national range and then adjusts for local conditions. National cost guides published in 2026 place most gas furnace replacements between about $3,500 and $7,500 installed.
Equipment pricing alone shows how wide the new furnace cost spread can be. A basic 80% AFUE, 80,000 BTU unit sells for roughly $1,260 to $1,635 at retail, while a comparable 96% AFUE model sits near $2,000 before installation. Labor for a standard replacement is commonly quoted between $1,500 and $3,500, depending on how much needs to change in the home.
Billings homes often see a new furnace cost in the middle to upper part of that range for three reasons:
- Cold design temperatures: Billings dropped to -31°F in January 2024, its coldest reading since 1999, according to the National Weather Service in Billings. Furnaces here need enough capacity for those nights.
- High-efficiency demand: Many homeowners choose 95% AFUE or higher because the heating season is long.
- Venting updates: Switching from an older 80% furnace to a condensing model usually means new PVC venting and a condensate drain.
New Furnace Cost Breakdown: Where Your Money Goes
Your new furnace cost is more than the price of the box in your basement. Breaking it into parts makes it easier to see why two quotes can look so different. The table below shows the typical cost pieces on a gas furnace replacement and what drives each one.
| Cost piece | Typical share of the bill | What changes the price |
|---|---|---|
| Furnace equipment | About 35% to 50% | BTU size, AFUE rating, single-stage vs two-stage vs modulating, variable-speed blower |
| Labor and installation | About 30% to 45% | Access (basement, attic, crawlspace), removal of the old unit, job length |
| Venting and drain | Varies | New PVC intake and exhaust for condensing furnaces, chimney liner for older setups |
| Ductwork changes | Varies | Transitions to fit the new cabinet, duct sealing, repairs found during the job |
| Thermostat and controls | Small | Basic vs smart thermostat, zoning controls |
| Permits and inspection | Small | Local permit fees and gas line inspection |
The percentages above are general guides, not fixed rules. A simple swap in an open basement costs far less to install than a tight attic job with new venting. That is why we always look at the home before giving a number.
How Furnace Efficiency Changes the Price
Efficiency has a big effect on new furnace cost. It is measured by AFUE, which tells you how much of the fuel becomes heat in your home. According to the U.S. Department of Energy, high-efficiency systems run from 90% to 98.5% AFUE, while older low-efficiency systems run only 56% to 70%.
That gap matters in Montana. A furnace that wastes 30% or more of its fuel during a long winter costs real money every month. ENERGY STAR reports that certified gas furnaces for northern states can be up to 18% more efficient than baseline models and save about $160 per year. For a deeper look at ratings, read our guide to AFUE ratings for Billings.
How Furnace Size Changes the Price
Bigger is not always better. An oversized furnace heats the house fast, shuts off, and starts again, which wears parts and leaves rooms uneven. An undersized furnace runs nonstop on the coldest nights. A proper Manual J load calculation looks at insulation, windows, square footage, and air leaks to find the right size. Correct sizing often lowers the new furnace cost because you are not paying for capacity you will never use.
Signs It Is Time to Budget for a New Furnace
Knowing the warning signs helps you plan for a new furnace cost on your schedule instead of during a January breakdown. Watch for these common signs:
- The furnace is 15 to 20 years old or older.
- Repair bills are coming more often and adding up fast.
- Gas bills keep rising even though your usage has not changed.
- Some rooms stay cold while others feel too warm.
- You notice yellow burner flames, soot, or a rusty cabinet.
- The system makes banging, rattling, or screeching noises.
- Your carbon monoxide alarm has sounded near the furnace.
If two or three of these sound familiar, it may be time to compare repair costs against a new system. Our guide on furnace repair or replace walks through that decision step by step.
Not sure where your furnace stands? Our licensed technicians can inspect it, explain what we find in plain language, and give you options for repair or replacement. Call Platinum HVAC at (406) 671-8446 to schedule a visit. We are here to help 24/7.
What Is the $5,000 Rule for a Furnace?
The $5,000 rule is a quick rule of thumb some homeowners use to decide between repair and replacement. You multiply the age of the furnace by the repair cost. If the result is more than $5,000, replacement usually makes more sense. For example, a 15-year-old furnace with a $400 repair gives you $6,000, which points toward replacement.
This rule is a starting point, not a final answer. It does not account for efficiency, safety, or how much longer the rest of the system will last. A cracked heat exchanger, for example, is a safety issue no matter what the math says. We use the rule as one input, then look at the whole system before making a recommendation.
How to Get an Accurate Furnace Quote in Billings
An accurate quote on your new furnace cost protects your budget and lets you compare contractors fairly. Follow these steps when you start shopping:
- Gather your basics. Note the age and model of your current furnace, your home’s square footage, and any comfort problems you have noticed.
- Ask for an in-home visit. A quote given over the phone cannot account for venting, duct condition, or access.
- Request a load calculation. Ask how the contractor will size the new furnace instead of matching the old one.
- Get an itemized written quote. It should list the equipment model, AFUE, labor, venting, permits, and warranty terms.
- Compare at least two options. Look at an 80% and a 95% or higher model so you can see the long-term trade-off.
- Ask about financing. Many homeowners spread the cost over time. Review our HVAC financing options before you decide.
Does a New Furnace Cost More Because of New Efficiency Rules?
Federal rules could shape new furnace cost over the next few years. The Department of Energy finalized a standard that would require new gas furnaces made after December 18, 2028 to reach 95% AFUE. A federal appeals court upheld that rule in November 2025, and in January 2026 the American Gas Association asked the Supreme Court to review it, according to the Air Conditioning Contractors of America.
Because the case is still being challenged, nobody can say for sure when or if the rule will take effect. What it means for you today is simple. If you are replacing a furnace now, choosing a 95% AFUE or higher model already meets that future standard. Most Billings homeowners we work with lean that way anyway because of how long our heating season runs.
What Is the Best Time of Year to Replace a Furnace?
Late summer and early fall are usually the easiest times to lock in a new furnace cost and replace a furnace in Billings. Contractors have more open dates, and you have time to compare quotes without a cold house pushing you to decide. Spring works well too, once the heating season winds down.
Emergency replacements in January are possible, and we handle them, but your choices may be narrower if a specific model is backordered. Planning ahead gives you the most control over the new furnace cost and the equipment you choose. If you are already in a no-heat situation, our emergency HVAC service is available around the clock.
Frequently Asked Questions
How long does a furnace last?
Most gas furnaces last about 15 to 20 years with yearly maintenance. Hard winters, dirty filters, and skipped tune-ups can shorten that life. A furnace that is regularly cleaned and checked tends to stay efficient longer.
Is it worth replacing a 30-year-old furnace?
In most cases, yes. A furnace that old is likely well below today’s efficiency levels, and the Department of Energy notes older systems can run as low as 56% to 70% AFUE. Parts may also be hard to find, and safety components wear out over time.
Should I repair or replace my furnace?
Repair usually makes sense for younger furnaces with a single, affordable problem. Replacement often makes more sense for furnaces over 15 years old with frequent repairs, rising gas bills, or safety concerns. A technician can show you the numbers for both choices.
Should I replace my furnace and AC at the same time?
Replacing both together can lower the new furnace cost on labor and make sure the systems match. It is not always necessary, though. Our article on replacing furnace and AC together explains when it pays off.
Planning Your Furnace Replacement With Platinum HVAC
The new furnace cost for your Billings home comes down to size, efficiency, and how much of the system needs to change. A clear, itemized quote takes the guesswork out of it. Platinum HVAC LLC is a family-owned company certified with Trane and Mitsubishi, and we explain every line of the quote before any work begins.
We serve Billings, Laurel, Lockwood, Shepherd, Huntley, and nearby communities. Contact us today to schedule a visit, or call (406) 671-8446 to talk with our team.