How much does an air conditioner cost?

Depending on where you live, air conditioning may be essential, a small luxury or rarely necessary — and this affects the type of system you need and the expected costs of replacement. It’s important to consider not only how much the unit itself costs, but also the costs of installation and ongoing maintenance and energy use.

Key insights

• There are four main options for home AC systems: central air, ductless mini-splits, window units and portable units.
• Central air and mini-splits cost the most upfront, but they’re also the most energy-efficient.
• AC units are rated for energy efficiency with the seasonal energy efficiency ratio (SEER) or combined energy efficiency ratio (CEER). As of Jan. 1, 2023, all central and mini-split systems sold in the U.S. must have a SEER rating of at least 14 or 15.

Types of air conditioners

Your AC replacement costs will depend largely on which type of system you need: central air, window unit, mini-split or portable unit.

Central air conditioning

Central air conditioning works by pulling air through intake vents in your home, running it through an outdoor condensing unit, then blowing the conditioned air back into the house through a network of ducting and vents.

Central AC systems are rated by their cooling power, measured in tons and British thermal units (Btu), with one ton equaling 12,000 Btu. For an average home, you’ll need approximately one ton of cooling capacity for every 400 to 500 square feet, but the same capacity might work for 800 to 1,000 square feet in an energy-efficient home.

Window units

A window unit is a small AC system that can be set up in most windows. The closed system uses an internal fan to blow cool, condensed air into the house and vent hot air outside. Window units range from around 5,000 to 25,000 Btu. Most can be plugged directly into a wall outlet, but the largest units may require a dedicated circuit.

Ductless mini-splits

A ductless mini-split is a two-part system that works as both an air conditioner and a heater. It consists of an indoor, wall-mounted unit (called a “head”) and an outdoor condenser unit.

Like a central air system, the condensing unit typically sits on a platform outside your house next to an exterior wall. Each condenser can support up to four heads, and each head can be controlled independently. Mini-splits are the most energy-efficient systems on the market, with SEER ratings up to 30.

Portable units

A portable AC unit is intended to cool only one room, and it must be set up next to an outlet with access to a window to vent the hot air outside. Portable units can be moved from room to room, are easily stored in the offseason and are ideal for those living in mild climates.

» MORE: How solar-powered air conditioning works

Factors that affect air conditioner costs

There are several factors that influence the cost of an air conditioner. The first is the size of the unit, with higher-capacity systems costing the most. If you’re considering a mini-split system, the more heads you add, the higher your costs.

You’ll also see price differences based on the brand —while you may have brand loyalty, you should always read reviews and ask friends and neighbors for recommendations.

Michael Jesdtadt, the owner of Smart Heating and Air Conditioning in Pittsburg, California, explained: “There is typically a strong correlation between a higher warranty and a higher-quality product. Saving money upfront on a cheaper unit and installation can end up costing more down the road on unexpected breakdowns and inconveniences.”

Two other major factors are your installation needs (installing new ducting or repairing existing ductwork can add thousands to your total) and the overall energy efficiency of your home. Things like your home’s insulation, window seals, ventilation and shading can all have a significant impact on how well your system is able to cool your home.

» MORE: Best home warranties for HVAC

Central air unit costs

Upfront costs for central air include both the price of the unit itself and the labor to install. You’ll see the most variation based on the size of the unit and whether you need new ductwork.

If there’s existing ductwork, you can expect to pay anywhere from $3,000 to $15,000, with an average cost of $7,000. Still, you should always have your ducting inspected for leaks, asbestos or mold. There are also plumbing and electrical costs to factor in; the system requires a permanent drain line to collect condensation and needs to be hard-wired to a dedicated circuit.

Maintenance costs

A professionally installed central AC system should last 15 to 20 years with regular maintenance (replacing air filters every few months and protecting the condenser in the offseason). The outside condenser should be covered in winter, and dust and debris should be cleared away before use in the spring or summer. Most professionals recommend an annual inspection, which can cost anywhere from $80 to $250 per visit.

Energy costs

Energy costs for central air vary greatly, depending on how often your system runs and its SEER rating. Based on an average use of 1,000 hours a year, a system with a 13 SEER rating costs approximately $243 a year to run, while a 15 SEER system costs around $210, according to the U.S. Department of Energy.

Window unit costs

Window units are designed for users to install on their own, so the only initial cost to consider is the unit itself, which can run from $170 to $850. The unit cost depends on the Btu rating, and you need approximately 20 Btu to cool one square foot of living space.

Maintenance costs

Almost all maintenance for window units can be done by the homeowner, including regularly checking and cleaning the filter and cleaning the evaporating coils using the brush attachment on your vacuum cleaner.

Energy costs

Based on an average life span of 9.3 years, a 6,000- to 8,000-Btu  window unit costs between $37 and $66 per year to run (depending on the CEER rating, which ranges between 11 and 20.2).

Ductless mini-split costs

As with central air systems, the cost to install a mini-split will vary widely, depending on how complex your system is. Most experts we consulted quoted between $3,000 and $5,000 to install a single condenser and head, but if you need multiple heads it can cost upward of $25,000.

Maintenance costs

Like all AC systems, you’ll need to clean the filters regularly, wipe down or vacuum the condensing coils and keep both the internal and external units uncluttered and free of debris. HVAC experts recommend cleaning the filters on mini-splits as often as every two to three weeks. For optimal performance, you should have each head professionally inspected at least once a year.

Energy costs

The benefit of mini-split systems is they don’t use ducting, which can consume up to 30% of your energy. For a 12,000-Btu unit, you can expect to pay roughly 26 cents per hour in energy costs, or $260 per year, based on an average use of 1,000 hours.

Portable air conditioning costs

With a portable unit, there’s no real installation process — though if the included venting hose isn’t long enough, you may need to purchase a longer one for $20 to $30. A 5,000-Btu portable unit costs around $250, while a 10,000- to 12,000-Btu unit can cost over $800.

Maintenance costs

Portable units need basic maintenance, like cleaning of the filters and coils and ensuring the hot air is properly vented.

Energy costs

Assuming an average life span of 10 years, you can expect to pay $99 a year to run an average-efficiency portable unit, but you might spend as little as $53 a year if you have a high-efficiency model.