Quick answer: Central AC replacement cost usually runs about $5,000 to $8,300 installed for a standard-efficiency system, with mid-range systems at about $8,300 to $12,500 and high-efficiency systems at $14,000 or more. Replacing the AC and furnace together typically costs $10,500 to $18,500. Size, efficiency (SEER2), ductwork condition and local labor rates move the price the most.
A new air conditioner is one of the bigger checks most homeowners write, and prices vary more than people expect. Two quotes for the “same” 3-ton system can be thousands apart because of equipment brand, efficiency, what’s included and how much the installer has to change.
The numbers below come from 2026 national cost data published by HomeGuide and Angi. Use them as a starting point, then get local quotes, because labor rates, permits and climate make a real difference.
AC replacement cost at a glance
| System | Typical installed cost |
|---|---|
| Standard-efficiency central AC | $5,000 to $8,300 |
| Mid-range efficiency central AC | $8,300 to $12,500 |
| High-efficiency central AC | $14,000 and up |
| Central AC plus new ductwork | $9,000 to $16,000 |
| AC and furnace replaced together | $10,500 to $18,500 |
| Air-source heat pump (heats and cools) | $8,000 to $15,000 |
Angi puts the national average for AC replacement at about $6,000, though that figure includes all types of air conditioners, not only central systems.
Cost by system size
Central air conditioners are sized in tons of cooling (1 ton equals 12,000 BTU per hour). Bigger homes and hotter climates need bigger systems. Here are HomeGuide’s installed ranges for standard systems:
| Size | Typical installed cost |
|---|---|
| 1.5 tons | $4,700 to $6,500 |
| 2 tons | $5,000 to $6,800 |
| 2.5 tons | $5,400 to $7,200 |
| 3 tons | $5,800 to $7,800 |
| 3.5 tons | $6,200 to $8,300 |
| 4 tons | $6,500 to $8,800 |
| 5 tons | $7,000 to $9,500 or more |
Bigger isn’t better. An oversized system cools fast but shuts off before removing humidity, leaving the house clammy and wearing out parts. A good contractor calculates the right size with a load calculation, often called a Manual J, instead of just matching the old unit.
Cost by efficiency (SEER2)
SEER2 measures how efficiently an AC cools over a season. Higher numbers use less electricity but cost more upfront.
| Efficiency | Typical installed cost |
|---|---|
| Up to 13.4 SEER2 | $5,300 to $7,900 |
| 14.0 to 14.7 SEER2 | $6,700 to $9,300 |
| 15.0 to 17.2 SEER2 | $7,500 to $10,600 |
| 16.5 to 18.5 SEER2 | $9,100 to $12,200 |
| Up to 25.8 SEER2 (variable speed) | $11,400 to $17,300 or more |
Federal minimum efficiency rules differ by region, and the southern states have higher minimums than the north. Your contractor will know what’s required where you live.
Higher efficiency pays back fastest in hot climates where the AC runs most of the year. In a mild climate with short summers, a mid-range system is often the better value.
What drives the price up
- Ductwork problems. Ducts that leak, are undersized or are falling apart can add $300 to $1,500 for repairs and sealing, or $1,400 to $5,600 or more to replace.
- Replacing the furnace or air handler too. A new outdoor unit matched with an old indoor coil or furnace may not reach its rated efficiency.
- Electrical upgrades, such as a new disconnect, breaker or wiring.
- A new refrigerant line set if the old lines can’t be reused.
- Permits, often $100 to $250, or more if ductwork is involved.
- Hard-to-reach equipment in attics or crawlspaces.
- Peak season. Summer emergencies can cost more and take longer to schedule.
New refrigerant rules have also pushed equipment prices up. Since 2025, new residential systems have been moving to lower-impact refrigerants, and the new equipment generally costs more than older models did.
Should you replace the furnace at the same time?
Often, yes. ENERGY STAR notes that a new air conditioner only performs at its rated efficiency when its components are matched, and it especially recommends replacing the heating system at the same time if your furnace is more than 15 years old. Replacing both together also saves on labor compared with two separate jobs.
Repair or replace?
Consider replacing your AC when:
- It’s more than 10 to 15 years old. Central air conditioners typically last 12 to 17 years.
- It needs a major repair such as a compressor or evaporator coil. Angi puts most AC repairs at $450 to $2,000 or more.
- It uses R-22 refrigerant, which is no longer produced, making repairs expensive.
- Your energy bills keep climbing, or some rooms never cool well.
- You’ve needed several repairs in the last few years.
A common rule of thumb: multiply the system’s age by the repair cost. If the result is over $5,000, replacement usually makes more sense.
How to get a fair AC replacement quote
- Get three written quotes from licensed, insured HVAC contractors.
- Ask for a load calculation rather than a size based on your old unit or square footage alone.
- Compare the same things: brand and model numbers for both the outdoor and indoor units, SEER2 rating, and whether the thermostat, line set, pad, permit and haul-away are included.
- Ask about warranties: the manufacturer’s parts warranty (and whether it requires registration) and the contractor’s labor warranty.
- Check for rebates from your utility and any available tax credits for high-efficiency equipment.
- Replace before peak season if you can. Spring and fall bring more scheduling flexibility.
Frequently asked questions
How much does it cost to replace a central AC unit?
Most central AC replacements cost about $5,000 to $8,300 installed for a standard-efficiency system in 2026. Mid-range systems run about $8,300 to $12,500, and high-efficiency systems can cost $14,000 or more.
How much does a 3-ton AC unit cost installed?
A standard-efficiency 3-ton central AC typically costs about $5,800 to $7,800 installed. Higher-efficiency 3-ton systems cost more, and ductwork or electrical upgrades add to the total.
Is it cheaper to replace the AC and furnace together?
Per system, usually yes. Replacing both together typically costs $10,500 to $18,500, and you save on labor while making sure the indoor and outdoor equipment are properly matched.
How long does an AC unit last?
Central air conditioners typically last 12 to 17 years. Regular maintenance, a properly sized system and a good installation help it reach the upper end of that range.
Is a higher SEER2 rating worth the extra money?
In hot climates where the AC runs much of the year, higher efficiency often pays for itself through lower electric bills. In milder climates, a mid-efficiency system is often the better value.
How long does AC replacement take?
A straight replacement of the outdoor unit and indoor coil usually takes one day. Jobs that include a new furnace, ductwork or electrical upgrades can take two to three days.
Do I need a permit to replace my AC?
In most areas, yes. Permits typically cost $100 to $250 for a basic replacement and more when ductwork is involved. Licensed HVAC contractors normally pull the permit and schedule the inspection.
What size AC do I need for my house?
It depends on your home’s square footage, insulation, windows, sun exposure and climate. A contractor should run a load calculation (Manual J) rather than guess based on square footage or your old unit’s size.
When is the best time to replace an AC?
Spring and fall are usually the best times. HVAC contractors are less busy, so you have more time to compare quotes and schedule installation without a summer emergency.
Should I repair or replace a 15-year-old AC?
If a 15-year-old system needs a major repair like a compressor or coil, replacement is usually the better value. Older systems are also less efficient and may use refrigerant that’s expensive to service.
Get local AC replacement quotes
National ranges only go so far. The fastest way to know your real AC replacement cost is to get quotes from contractors in your area. Compare HVAC contractors near you on We Got Your Guys, check their reviews and licenses, and call them direct.