How much does it cost to install a natural gas furnace?

National Average Range:
$4,000 - $8,000

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Updated: August 17, 2022

Reviewed by Adam Graham remodeling expert. Written by

To provide you with the most accurate and up-to-date cost figures, we gather information from a variety of pricing databases, licensed contractors, and industry experts.

If you heat your home with forced hot air, then you need to install a furnace to convert energy into heat. Furnaces are available in many fuel types, with gas units being one of the most popular. Gas furnaces have the lowest ongoing monthly expenses, making them a good choice for those who want to heat their homes on a budget.

Gas furnaces have a range of costs, depending on the unit size and how efficient it is, with larger and more-efficient models costing more upfront. Labor fees for installation also vary depending on whether there is a gas line present and how complex the installation is. The average cost range for purchasing and installing a gas furnace designed to heat a 2,000-square-foot home with a 97% efficiency rating ranges from $4,000 to $8,000, with most homeowners spending around $6,000 total on a high-efficiency gas furnace replacement in a 2,000 sq.ft. home with minor modifications. This project’s low cost is $3,000 for a moderate-efficiency gas furnace replacement in a 2,000 sq.ft. home with no modifications. The high cost is $12,000 for a high-efficiency furnace replacement with new ductwork for a 2,000 sq.ft. home.

Gas Furnace Prices

Gas Furnace Installation Cost
National average cost$6,000
Average range$4,000-$8,000

What Is a Gas Furnace?

Gas furnaces are an HVAC system designed to heat your home using forced hot air, with natural gas as the fuel. It is brought to your home through a pipeline, with a branch feeding into your furnace. It burns the gas to heat air. This air is forced through a series of ducts in your home, entering each room through vents. They use the same ducts and vents that central air conditioners use. They come in many sizes and efficiency levels, letting them work in most homes.

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Gas Furnace Cost By Type

Gas furnaces come in three basic types, impacting the system’s efficiency. These are single-stage, two-stage, and modulating systems. Single-stage are the most basic and least expensive but are the least efficient of the three. Modulating systems are the most expensive and energy-efficient, so you use less gas each month. Each type comes in several sizes to meet your home’s needs.

Cost per Unit of a Single-Stage, Two-Stage, and Modulating Gas Furnace (mobile)

TypeAverage Costs per Unit (Materials Only)
Single-Stage$500 - $1,700
Two-Stage$700 - $2,700
Modulating$1,200 - $3,500

Single-Stage Gas Furnace

The cost of a single-stage gas furnace is $500 to $1,700. Single-stage furnaces were the first type ever produced. They are still used today, but many people choose not to use them because of their lower efficiency, lower comfort, and noisier operation. In a single-stage system, the blower can turn on and off. It has one speed, so it heats your home, and then shuts off. When the temperature falls too low, it turns on again. Your home will have cold spots, there will be long times between the furnace turning off and on, and it will be noisy.

Two-Stage Gas Furnace

The cost of a two-stage gas furnace averages $700 to $2,700. Two-stage furnaces have two settings for their blower - high and low. This means they can cycle on and off more frequently while using less energy. Your home stays more comfortable, and your energy bills are lower. They are usually quieter because they have a lower setting used to maintain the temperature. The high setting is only used to get your home to temperature when you first turn it on at the start of the day.

Modulating Gas Furnace

The cost of a modulating gas furnace ranges from $1,200 to $3,500. Modulating furnaces are among the most efficient, often reaching 98% efficiency or higher. They are also the most comfortable because they rarely shut off. They blow more or less hot air to keep your home at an even temperature. There are no cold zones or dropping temperatures. It also uses less fuel because it does not have to work as hard to bring the temperature back again.

What Size Gas Furnace Do I Need?

Not every furnace has the same amount of output. Heat output is measured in British thermal units (BTUs). The more BTUs, the more heat your furnace is capable of generating. Homes that are larger, have more than one floor or are located in cold climates need more BTUs than houses that are smaller, have only one floor, or are located in warm climates.

Generally, you calculate the load for your furnace based on two things: your home’s total square footage of finished, heated space and the region or climate your house is located in. Region 1 is the hottest, which includes most southern parts of the country, while Region 5 is the northern, coldest area. Consult the U.S. Energy Information Administration’s climate zone map to determine your zone number.

First, calculate the interior square footage of the heated areas of your home. Start by measuring the length and width of each room and multiply them together to calculate the square footage. Add up the square footage of all the rooms to get your total square footage. Then, multiply this by the number of BTUs needed per square foot for your region. Colder regions require more BTUs to heat the same-size space as homes in warmer regions.

BTUs Needed to Heat One Sq.Ft. in Zones 1, 2, 3, 4, 5, 6, and 7

ZonesBTUs per Square Foot
Zone 130 - 35
Zone 235 - 40
Zone 340 - 45
Zone 445 - 50
Zone 550 - 60

So a 2,000-square-foot home located in Texas would need a furnace capable of 60,000 BTUs, while the same-sized house in Wisconsin would require one capable of 120,000 BTUs. This means the furnace for the Wisconsin home would be larger and, therefore, more expensive.

To get a general idea of how large a furnace you will need, the following chart shows how many BTUs are required for homes of different sizes in a Zone 4 climate.

BTUs per Hour Needed to Heat an 800, 1,000, 1,200, 1,500, 2,000, and 2,500 Sq.Ft. House (mobile)

Square FootageBTUs
800 sq.ft.36,000 - 40,000
1,000 sq.ft.45,000 - 50,000
1,200 sq.ft.54,000 - 60,000
1,500 sq.ft.67,500 - 75,000
2,000 sq.ft.90,000 - 100,000
2,500 sq.ft.112,500 - 125,000

Ideally, you want to get within 10% of these figures for your home’s size and region when purchasing a furnace for the best efficiency. Do not go more than 20% over because this can cause your furnace to work harder than necessary, driving up energy bills and lowering its lifespan.

High-Efficiency Gas Furnace Cost

Regardless of what unit type you have, it will have a rating that lets you know how efficient it is at converting energy into heat. This is known as the annual fuel utilization efficiency (AFUE). Each has a rating as a percentage of the amount of fuel it converts to heat - the higher the number, the better the efficiency.

Furnaces are considered high-efficient if they are rated at 90% or above, while a standard furnace is considered to be 80% to 89% efficient. These furnaces also have a blower that helps circulate the air through your home more efficiently. You can now find gas furnaces with up to 98% efficiency, although they tend to have higher costs than high-efficiency oil or propane furnaces. The price of a high-efficiency unit installed is around $6,000 but can go as high as $10,000, depending on the size and the efficiency you want. Labor costs are usually slightly higher for high-efficiency units due to the need for a drain in many instances. The closer you get to 100%, the higher your material costs are.

Comparison of the Cost per Unit of a Standard and a High-Efficiency Gas Furnace (mobile)

Furnace EfficiencyAverage Costs (Materials Only)
80% - 89% (Standard)$500 - $1,700
90% - 98% (High-Efficiency)$700 - $3,500

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Natural Gas Furnace Prices by Brand

Many different brands of gas furnaces are on the market. Most are available at your local big-box store, but others may be available through your heating provider. Brands may have different attributes making one better for your home. Some may specialize in energy efficiency, while others may have better warranties. The following are some of the top brands that receive consistently good reports. Costs are for material only and do not include installation.

Cost per Unit of a Rheem, Ruud, Bryant, Carrier, American Standard, Lennox, and Trane Gas Furnace (mobile)

BrandAverage Costs per Unit (Materials Only)
Rheem$800 - $1,500
Ruud$800 - $2,000
Bryant$800 - $2,500
Carrier$1,000 - $2,600
American Standard$1,200 - $2,500
Lennox$1,200 - $3,000
Trane$1,300 - $3,000

Rheem Gas Furnace

The cost of a Rheem gas furnace is $800 to $1,500. Rheem makes a series of furnaces. Most are single-stage, with a small number of two-stage and modulating. Rheem units have efficiency values of between 80% and 96% for some of their top lines. They are considered a good-quality budget furnace and are frequently used by builders.

Ruud Gas Furnace

The cost of Ruud gas furnaces averages $800 to $2,000. Ruud is made by the same company that makes Rheem. They share many of the same parts and casings. Like Rheem, they are primarily single-stage furnaces, with a small number of two-stage and modulating. They have efficiency ratings ranging from 80% to 97%. Ruud is considered to be slightly higher-end than Rheem and thought of as a dependable furnace by contractors.

Bryant Gas Furnace

The cost of Bryant furnaces ranges from $800 to $2,500. Bryant is a subsidiary of the Carrier brand. They share parts and casings with most Carrier furnaces. They have three separate model series, with one-stage, two-stage, and modulating units available. They have efficiency ratings ranging from 80% to 95%. Bryant is considered a good-quality budget line of furnaces that are dependable and long-lasting.

Carrier Gas Furnace

The cost of Carrier gas furnaces is $1,000 to $2,600. Carrier is part of the same company as Bryant and shares the same parts and casings. Like Bryant, they have energy ratings of between 80% and 95% on most models. They have more product lines, with the vast majority being one-stage. They have a single line of modulating furnaces and several two-stage lines. Like Bryant, Carrier is considered to be a good-quality and dependable line of furnaces.

American Standard Gas Furnace

The cost of American Standard gas furnaces is between $1,200 and $2,500. American Standard is owned by the same parent company as Trane. The American Standard brand is considered the lower-cost option from the company’s Trane flagship brand. They have three lines of furnaces - silver, gold, and platinum. Their silver series is the least expensive and consists mostly of single-stage units. Gold is mid-range and has many two-stage units, while platinum is their highest-quality line with modulating furnaces.

Lennox Gas Furnace

The cost of Lennox gas furnaces averages $1,200 to $3,000. Lennox has a line of very high-quality, high-efficiency furnaces. Their top-of-the-line models can achieve efficiencies of better than 98.7%. They also have a range of fairly efficient stage-one, stage-two, and modulating systems. Lennox is considered an innovator in the field. In addition to their standard ones, they also have a line that can use solar power as backup, increasing efficiency further.

Trane Gas Furnace

The cost of Trane gas furnaces ranges from $1,300 to $3,000. Trane is the luxury line of furnaces from the American Standard brand. They have several high-efficiency models and good-quality standard models. Trane units are mostly recommended for very cold climates that need higher efficiency because of the higher upfront costs. They are also recommended for people who are not moving or selling their home within 5 years to recoup the additional costs. Trane claims theirs can modulate humidity and ensure more comfortable heating for the entire home.

Gas Furnace Replacement Cost

Gas furnaces are fairly straightforward to replace, particularly if you are using the same basic make, model, and unit size. For some higher-efficiency models, there may be some additional installation costs, depending on the model. In addition, some higher-end brands have higher installation costs because the installer needs to undergo specialized training. This can make switching to a more efficient, high-end unit slightly more expensive in labor than it is to swap out a basic unit for the same type. On average, replacement costs for a gas furnace to a new unit of the same source fuel have similar averages of $4,000 to $8,000, with most people paying around $6,000 for an installed high-efficiency gas furnace. Labor costs range from $500 to $3,000, depending on whether modifications are needed. Most modifications include adding a drain, changing vents, and refitting the ducts to the new one. Using the same brand and size can keep replacement costs down, while changing brands and size may increase labor costs.

Keep in mind that most of the time when a furnace fails, it is a relatively easy repair. And while newer models are more efficient, it will generally save you money in the long run to make repairs instead of replacing. The only time replacement is recommended is when a major component of the furnace needs to be fixed, such as the heat exchanger or control module. Both of these are expensive and difficult to repair, and you still may need to replace the furnace when you are done.

Labor Costs to Install a New Gas Furnace

Labor costs for a gas furnace installation vary depending on the installation complexity. For example, installing a vent makes the furnace more difficult and time-consuming to install, which results in a higher cost. Furnace installations can have labor costs that range from $500 to $3,000, depending on the project complexity. Most people pay between $1,500 and $2,000 for labor on a new installation. Costs for installation and replacement are very similar. While each project has different attributes and work, the amount of labor is roughly the same in manpower and hours, making the average installation and replacement labor costs in the same range.

The installation process for a gas furnace varies slightly from home to home, depending on a few factors. If there is no gas line currently extending to the house, then a plumber will be required to run one to the new furnace. This can increase the project costs by $500 to $2,000. The furnace will also need an exhaust. So if there is not an exhaust source already, one will need to be installed through the wall near where the furnace will be placed. Finally, if there are no ducts or insufficient ones, then new ductwork will also need to be installed. The cost of new ducts ranges from $1,900 to $6,000, depending on whether these are new ducts or a replacement.

Otherwise, the installation is fairly straightforward. The old unit is disconnected from the fuel line, and the vent and ducts are removed. The new furnace is brought in, wired to the home’s electrical system, and the gas line is connected. The furnace is vented out the side of the house and connected to the ducts. If necessary, a new thermostat may also be installed. The entire process takes 2 to 3 hours on average.

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Cost of a New Gas Furnace Installed by Location

Gas furnaces can be installed in many residences, including single-family homes, apartments, condos, and townhouses. The costs for each project depend largely on the dwelling type, size, and where the unit is located. As long as a natural gas line is available for the area, you can install a gas furnace there. The following costs are for a new furnace installed in several types of residences.

Cost to Install a Gas Furnace in a Tiny House, Apartment, Mobile Home, Condo, Townhouse, Cottage, and House (mobile)

LocationAverage Costs (Installed)
Tiny House$1,000 - $2,500
Apartment$1,300 - $1,500
Mobile Home$1,300 - $1,500
Condo$1,500 - $1,700
Townhouse$1,700 - $2,500
Cottage$1,700 - $4,500
House$4,000 - $8,000

Tiny Home Furnace

The cost of installing a gas furnace in a tiny home ranges from $1,000 to $2,500. Tiny homes range from 100 to 500 sq.ft. This means the size can change dramatically. These costs are for the complete installation of the furnace system, meaning the unit, ducts and vents, and an exhaust. In some cases, a small wall furnace may be adequate for very small tiny homes. Only tiny homes on foundations in areas that receive natural gas can have this furnace.

Apartment Furnace

The cost to install a furnace in a single apartment is $1,300 to $1,500. Apartments can be heated in many ways. Some use furnaces and ducts, and of those, a small number uses a separate furnace and duct system for each unit. This is most common in older homes that have been divided into apartments and small apartment buildings. Larger apartments tend to use whole building systems for better efficiency. Single apartment furnaces are generally fairly small. They are designed to fit into closets or cabinets with limited runs of ductwork, which can mean lower overall costs.

Mobile Home Gas Furnace

The cost of a mobile home gas furnace averages $1,300 to $1,500. Mobile homes are much smaller than traditional stick-built homes. You do not need nearly as large a furnace, significantly lowering purchasing and installation costs. Other than size, mobile homes generally have the same type of installation as a standard-sized home. The unit is usually installed inside of a small closet, and duct runs are usually short. This makes installation quick and easy in most homes.

Condo Furnace Replacement

The cost of replacing a furnace in a single condo is $1,500 to $1,700. Most condos have their own furnace rather than relying on the entire building’s HVAC. The furnace is usually small and installed in an accessible closet. This makes replacement fairly easy and straightforward. Costs vary depending on whether modifications need to be made to the area when replacing the old furnace. In addition, some companies charge an additional fee for the old furnace’s removal and disposal - up to $200, but many do this at no cost.

Townhouse Furnace

The cost of a townhouse furnace is between $1,700 and $2,500. Townhouses are also fairly small buildings that do not require the same size as a standard home. However, they are generally two stories. They also generally have slightly more square footage than the average condo. This means the furnace must be slightly larger to supply the necessary heat. This makes the overall costs more than installing a furnace in a condo but lower than installing in a single-family standard-sized home.

Small Gas Furnace for a Cottage

The cost of a small gas furnace installation in a cottage averages $1,700 to $4,500. Cottages were once considered small buildings. But today, a cottage can exceed the size of many single-family homes. Even assuming the cottage is smaller than the average single-family home, it still leaves leeway for size changes. Therefore, you can have a wide range of costs for furnaces and their installation. Cost factors include the cottage size, location, and how many stories it has.

House Gas Furnace

The cost of installing a gas furnace in an average-sized home ranges from $4,000 to $8,000. This assumes a home that is roughly 2,000 sq.ft. Smaller homes and larger homes fall outside this price range. Most homes have one installed in the basement or lower level. It works by pushing hot air through ducts reaching into every room. If your home does not have ducts installed, your costs are higher because the ducts must be installed along with the furnace. If there are already ducts in place for an air conditioner, your new unit can use them.

Cost to Convert to Natural Gas Heat

If you have recently gotten a natural gas line, you may want to switch your current heating system to natural gas. Natural gas is generally less expensive to heat with when compared with propane, oil, and electricity. This fuel is not available in all areas, so some people may need alternative fuels. The cost of converting your current system to natural gas varies, depending on what you are currently using.

Cost to Convert a Propane, Electric, and Oil Furnace, and a Heat Pump to a Natural Gas Furnace (mobile)

ConversionAverage Costs (Labor Included)
Propane to Natural Gas$1,200 - $2,100
Electric to Natural Gas$4,500 - $8,000
Heat Pump to Natural Gas$4,500 - $8,000
Oil to Natural Gas$5,500 - $10,000

Convert a Propane Furnace to Natural Gas

The cost to convert a propane furnace to natural gas is $1,200 to $2,100. If you have an existing propane furnace and your area has recently had a gas line added, you can save a lot of money on your heating costs each month by converting to gas. The actual conversion is simple, with many units capable of using either fuel. The switch is made using a small conversion kit costing between $25 and $100. Some gas furnaces can run on propane or gas without this conversion, depending on the brand and type.

The real cost comes in running the gas line from the main line to your home. Installing a gas line from the main line to your unit costs around $500 to $2,000.

Convert From Electric to a Gas Furnace

The cost to convert from an electric to a gas furnace averages $4,500 to $8,000. Electric furnaces are mostly recommended for mild to moderate climates. They are not typically used in very cold climates because running costs become much higher than oil and propane. Most electric furnaces are smaller than other types. When converting to gas, you need a similarly sized small unit. You also need a gas line installed for $500 to $2,000 plus labor and the furnace’s cost. You may also have to pay for a drain, depending on your furnace’s efficiency.

Convert a Heat Pump to a Gas Furnace

The cost to convert a heat pump to a gas furnace ranges from $4,500 to $8,000. If you currently heat your home with an electric heat pump, you can save a lot of money each month by switching to a gas furnace. Gas units are much more efficient and do a better job of heating your home, particularly if you live in a colder region.

If you do not already have a gas line, you need one run to your home, which has starting costs of around $500 to $2,000. You will then need to purchase and install the new gas furnace, for a price of about $6,000 for a high-efficiency unit or approximately $4,000 for a lower-efficiency unit. Given that electric heat pumps are typically only used in zones 1 and 2, you should use a smaller furnace.

Convert an Oil Furnace to Natural Gas

The cost to convert an oil furnace to natural gas is between $5,500 and $10,000. Oil furnaces are typically used in the Northeast and other cold climates. They are most often used in areas without current access to natural gas. If you get a gas line in your area, you can extend it to your home for $500 to $2,000. You then must replace your current unit with one that can handle natural gas. You also must clean your ducts and surrounding system because oil produces a lot of soot. Natural gas burns much cleaner, so your ongoing maintenance is much lower.

How Much Does It Cost to Run a Gas Furnace for an Hour?

To get an idea of how much your gas furnace would cost to run for an hour, you need to consider several things, including the cost of gas where you live and the size of your unit. Keep in mind that this can only give you a very general idea of how much it costs to run, and to truly calculate your exact cost per hour, you need to watch your gas meter to see exactly how much gas is being used. This is because the amount of gas each one uses varies depending on its efficiency rating, with higher-efficiency models using less gas than lower efficiency models.

A very general way to get a ballpark of how much it costs to run for an hour, find your furnace’s BTUs and the gas cost per cubic foot in your area. One cubic foot of gas is needed for 1,030 BTUs. For a 100,000 BTU furnace, you will use 97 cubic feet per hour.

Gas is sold in units of 100 or CCF, so you will need to divide 97 cubic feet by 100 to get .97 CCF per hour. Now, multiply the cost of one CCF of gas by .97 to get the average price to run a furnace for one hour. This does not factor in the high efficiency of some units. For that, you need to determine exactly how much gas your furnace uses by watching your gas meter.

The current national average cost of 1 CCF of gas is $1.41, resulting in a price of $1.36 an hour. Your area’s gas prices could be much higher or lower than this, so to get a more accurate number, call your gas company for more information.

Natural Gas Furnace Closeup

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Gas Furnace Air Conditioner Combo Cost

If you live in an area where you will also have high summer temperatures, you may want to consider installing an HVAC system that can heat and cool your home from one unit. This can be more efficient and easier to install than some other methods. This is different than using separate air conditioning units and furnaces - these are single units that handle both needs. They are not as efficient as separate systems. You may also have higher repair costs and more maintenance because the single system runs more frequently than two separate systems.

Like furnaces, there can be a range of costs depending on the unit’s efficiency and size. This means the average range of installing a gas furnace/air conditioner combo is between $6,000 and $12,000. Most people pay around $9,000 for a high-efficiency unit capable of heating and cooling a 2,000 sq.ft. home.

Pros and Cons

Gas furnaces have some of the lowest yearly expenditures compared to other types. They are also one of the more environmentally friendly types of furnaces, letting off fewer emissions than oil or electricity. If you live in an area that can easily get natural gas, they are also usually fairly easy to hook up and install. They also do not require fuel storage like liquid propane or oil, so you do not have added expenses, such as tanks or delivery fees.

However, this type of unit is not available everywhere. Homes in rural areas do not normally have access to gas lines, making a gas furnace out of reach. They are also less efficient than other types. While they can now reach 95% efficiency in some of the newest models, these tend to be very expensive. Getting a similarly efficient - or more efficient - furnace from another fuel type can cost a lot less up front.

Fire Burning in a Natural Gas Furnace


Gas furnaces are fairly low-maintenance. You need to change the filter every 1 to 3 months, depending on the type and manufacturer’s recommendations. Otherwise, the unit should be serviced and cleaned yearly to keep it functioning well. Several areas of the unit may require cleaning. You can do this yourself, using this checklist to ensure you reach every area. Or, you can call your local installer and have it professionally cleaned and serviced. This costs roughly $100 to $150 per visit to ensure it is running correctly.

​​Electric vs Gas Furnace

Another option to heat your home is an electric furnace, and both electric and gas furnaces have their pros and cons. But due to the high cost of heating your home with electricity, electric furnaces are generally only recommended for regions 1 and 2 with partial use in region 3. If you live in a colder climate, you may not be able to find an electric furnace that is large enough and capable enough of handling the load. This is due to the higher costs to run an electric vs a gas unit.

For regions that do not use a lot of heat, however, an electric furnace is generally less expensive to install. They are also quieter to run and use nearly 100% of the energy fueling them, so while they do cost more to run, they are technically more efficient.

Depending on the area where you live, an electric furnace may also be better for the environment. This is because different areas produce electricity with different methods. If you live in an area that produces electricity mostly through hydropower or another eco-friendly method, then switching to an electric furnace can also be a greener option for your home.

Electric furnaces are less expensive to purchase and install than gas units, but they cost more to run. In addition, electric furnaces do not function well in cold areas, making them less useful. In cold climates, it is recommended to use a gas unit.

Comparison of the Cost to Install an Electric and a Gas Furnace (mobile)

TypeAverage Costs (Installed)
Electric$1,600 - $3,200
Gas$4,000 - $8,000

Oil Furnace vs Gas Furnace

Another option to consider is an oil furnace. Oil furnaces are generally a better fit for homes that do not have gas lines installed because they cost more to run than gas furnaces. The average cost to heat a home with gas is around $544, while the cost to heat the same house with oil is about $1,408 - a significantly higher amount. Oil furnaces also cost more than gas units to purchase and install.

However, if you do not have a gas line or access to a gas line, then an oil furnace can be a good choice. Oil is very efficient because it burns much hotter than gas, so you can heat your home for less fuel overall, which can be a better choice for the environment. They are also available in high-efficiency models that can help lower your overall fuel usage even more.

Oil furnaces require more maintenance than others because they produce a lot of soot. This means more frequent filter changes and more costly yearly maintenance to keep them clean and running at peak efficiency. They can also be more expensive to purchase and install than gas, so if you have the choice, a gas furnace will be less expensive to buy and install, less expensive to maintain, and will save you money on energy bills each month.

Comparison of the Cost to Install an Oil and a Gas Furnace (mobile)

TypeAverage Costs (Installed)
Gas$4,000 - $8,000
Oil$5,000 - $9,000

Gas Furnace vs Boiler

You have two options if you want to heat your home with natural gas: a natural gas furnace or natural gas boiler. These systems run on gas but work in different ways.

A furnace heats hot air and forces it through ducts to different rooms. This is called a forced hot air system, and it can use the same ducts as a central air conditioning system.

A boiler heats water and distributes hot water or steam to various rooms through pipes. The heat can be distributed through radiators or radiant floor heating. Once the hot water or steam has passed through the heating module, it returns to your boiler to be reheated and sent along again. If you want central air conditioning, you also need a series of ducts.

Both systems can heat your home, and both come in a range of efficiencies. Of the two, forced hot air is the most common, but many people find radiant heating through radiant flooring or radiators to be more comfortable because forced hot air can dry the air. Boilers are more common in cool weather areas where central air conditioning is not commonly used, while furnaces can be used anywhere if the home has ducts.

Of the two, a furnace is generally less expensive upfront. Boilers may be less costly to run long term, but this depends on your system’s efficiency and home size.

Below are the average costs to install a gas furnace and a gas boiler designed for heating a 2,000 sq.ft. home.

Comparison of the Cost to Install a Gas Furnace and a Boiler (mobile)

Heating SystemAverage Costs (Installed)
Gas Furnace$4,000 - $8,000
Boiler$5,000 - $10,000

Gas Furnace vs Heat Pump

Consider installing a heat pump if you are looking for supplemental heating or live in a moderate-to-warm climate. Heat pumps are a different heating system than gas furnaces, and they can be much less expensive to run long term. Heat pumps can use air, groundwater, or the earth to produce heat. They move heat from its source into your home using electricity.

Gas furnaces heat hot air directly and force it through ducts. Gas furnaces can be large enough and produce enough heat to warm homes even in the coldest climates, while heat pumps are generally recommended for mild-to-moderate climates.

Heat pumps can also be run in reverse, removing heat and transferring it outside to cool your house. Gas furnaces can only produce heat. You need to install a separate system if you want cooling.

While heat pumps can be less expensive to run, they are usually more costly to install. Your total costs depend largely on the type, with geothermal pumps costing the most and air source pumps costing the least.

Below are the average costs for installing a gas furnace and heat pump designed to heat the same-size home.

Comparison of the Cost to Install a Gas Furnace and a Heat Pump (mobile)

Heating SystemAverage Costs (Installed)
Gas Furnace$4,000 - $8,000
Heat Pump$5,000 - $30,000

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Enhancement and Improvement Costs

HEPA Air Cleaner or Humidifier

It is possible to add either a high-efficiency particulate air (HEPA) filter or a humidifier to your furnace. The idea is that these will make your air cleaner and more comfortable. However, most of the time, this is not recommended because they often do not perform as well on the furnace as they do as stand-alone appliances. Adding them can add up to $1,000 to the final cost.

Old Furnace Removal

The old unit removal is often included in the cost of the new furnace if you purchase the new one from the installer. When going through a third party, there may be an additional $25 to $200 fee.​ These costs are mostly for removal and disposal rather than additional labor.

Increased Electrical Power

If your new furnace needs more power than the old one, you may need a circuit upgrade. This will cost around $1,500 to $4,000 on average. Circuit upgrades allow your home to support higher-power appliances, meaning many homes benefit from this upgrade beyond the addition of a new furnace.

Programmable Thermostat

To get the most out of your new furnace, you may also want to upgrade to a programmable thermostat that sets the temperature based on the time of day and day of the week. They cost around $150 to $400. Programmable thermostats can save money on your energy bills.

Adding an Air Conditioner

You can also install a new central air conditioner. This unit uses the same ducts as the furnace, allowing your home to stay comfortable year-round. The average cost to add an air conditioner is $4,000 to $6,000.

Additional Considerations and Costs

  • Permit. Any replacement or reworking of your furnace or HVAC system will require a permit in most areas. Always check with your town or city hall for the most up-to-date guidelines. Speak to your contractor before installation.
  • Tax credit. Depending on the energy efficiency of your new unit and the age of your home, you may be eligible for a tax credit, which may be available for efficient systems. Check with an accountant to find out if your new system qualifies.
  • Alternative fuels. Most U.S. homes utilize gas units. Although, some northern states use oil, and rural areas may use liquid propane or wood-burning stoves because natural gas is not available in these areas.
  • Eco-friendly options. Buying a more eco-friendly furnace helps both the environment and your wallet. Solar panels, geothermal heat pumps, and wood-burning systems are all more eco-friendly choices.
  • Inspection. Some permits may require you to have your unit inspected. This costs between $250 and $400, depending on the level of inspection.
  • Gas line. If you currently have an electric, oil, or propane furnace and are converting to gas, you need to add a gas line at an additional $500 to $2,000.


  • How much does it cost to install a gas furnace and ductwork?

Installing a new gas furnace and ductwork costs upward of $10,000 to $12,000 in total. This depends on the type of unit and ducts and your home size.

  • How long does a gas furnace last?​

Gas furnaces can last 10 to 12 years on average. Some may last up to 15 years - check warranties to get a good idea of average lifetimes.

  • Should ductwork be replaced after 20 years?

This depends on the ducts. Some may only need to be sealed, while others may need more returns added. In some cases, you may need to replace ducts that are old, rusty, or extremely leaky.

  • Can you finance a new gas furnace?

Yes, some companies offer financing for the new furnace and the installation, depending on your credit score.​​ Speak to the installation company about your options.

  • Are gas furnaces efficient?

Yes, gas furnaces are very efficient. It depends on the unit, but many can achieve efficiency of up to 98%.

  • What is the difference between a single-stage furnace and a two-stage furnace?

Single-stage furnaces turn on and off. This means they spend more energy heating your home and allow it to get colder between cycles. Two-stage furnaces can have high and low settings to be more efficient and make your home more comfortable by cycling less frequently.