Central AC Installation Cost
Updated 24 March 2026
System types, house size estimates, SEER ratings, and rebates explained.
Quick answer
- Standard system: $3,500 to $7,500 installed on existing ductwork
- High-efficiency or ductless: $5,000 to $12,000
- New installation with ductwork: $7,000 to $15,000 or more
System Types and Costs
The type of system is the biggest cost variable after house size.
Central Split System
$3,500 - $7,500The most common setup. An outdoor condenser and indoor air handler connected by refrigerant lines. Requires existing ductwork. Reliable, widely serviced, and the default choice for most homes.
Heat Pump
$4,000 - $8,000Heats and cools using the same unit. More efficient than a furnace in mild climates. Eligible for the federal 25C tax credit (up to $2,000). Best value in USDA climate zones 4 and warmer.
Ductless Mini-Split
$3,000 - $10,000One outdoor unit connects to one or more indoor wall units. No ductwork needed. Ideal for additions, garages, or older homes without ducts. Cost scales with the number of indoor zones.
Package Unit
$3,500 - $7,000All components in one outdoor cabinet. Common in warmer climates, mobile homes, and commercial buildings. Easier to service but slightly less efficient than a split system at the same SEER rating.
Cost by House Size
Prices below assume a split system replacing an existing unit on existing ductwork. Add $4,000 to $8,000 if ductwork is not present.
| House Size | Typical AC Size | Equipment | Total Installed |
|---|---|---|---|
| Up to 1,000 sq ft | 1.5 to 2 ton | $1,200 - $2,500 | $3,000 - $5,000 |
| 1,500 sq ft | 2 to 2.5 ton | $1,500 - $3,000 | $3,500 - $6,000 |
| 2,000 sq ft | 3 to 3.5 ton | $2,000 - $4,000 | $4,000 - $7,500 |
| 2,500 sq ft | 4 ton | $2,500 - $5,000 | $5,000 - $9,000 |
| 3,000+ sq ft | 4 to 5 ton | $3,000 - $7,000 | $6,000 - $12,000 |
Sizing should always be confirmed with a Manual J load calculation. An oversized unit will short-cycle and leave your home feeling humid.
SEER Rating: Does It Matter?
SEER (Seasonal Energy Efficiency Ratio) measures how efficiently a unit cools over a season. Higher SEER means lower electricity bills, but costs more upfront. The minimum legal SEER rating in most of the US is 14 or 15 depending on your region.
SEER 14 to 16
No premiumMinimum legal standard for new installations in most states. Cheapest upfront. Meets the baseline but offers no energy savings advantage over a unit installed 10 years ago.
SEER 17 to 20
Add $500 - $1,500Mid-range efficiency. Uses 20 to 30% less electricity than a SEER 14 unit. A SEER 16 unit saves roughly $200 per year compared to SEER 14 in average climates. The payback on upgrading is typically 5 to 8 years.
SEER 21 and above
Add $2,000 - $4,000Premium efficiency. Uses 40 to 50% less electricity than a minimum-standard unit. Best for homes in hot climates (Texas, Florida, Arizona) or homeowners planning to stay 10 or more years. Often variable-speed compressors that also reduce humidity better than single-stage units.
New Installation vs. Replacing an Existing Unit
This is where costs diverge most sharply. The ductwork is the expensive part.
Replacing an existing unit
- Existing ductwork stays in place
- 1-day job for most contractors
- Cost is mostly equipment and labor to swap units
- May need duct inspection if system is 15+ years old
- Permits typically $100 to $300
New installation with ductwork
- Ductwork alone costs $4,000 to $8,000 for a typical home
- 2 to 3 day job minimum
- Requires cutting through walls and ceilings
- Finished basements and crawl spaces increase cost
- Consider ductless mini-splits as an alternative
Federal Tax Credits and Rebates
Several programs can reduce your out-of-pocket cost significantly, especially if you choose a heat pump.
Federal 25C Tax Credit
Up to $2,000Qualifying heat pumps receive a 30% tax credit, capped at $2,000 per year. Standard AC units (air conditioners only) qualify for up to $600 if they meet efficiency thresholds. Applies to primary residences. Claim on IRS Form 5695. Available through at least 2032.
Utility Rebates
$200 - $1,000Many electric utilities offer rebates for upgrading to high-efficiency systems. Rebates are typically $200 to $1,000 depending on the SEER rating and utility. Check your utility's website or the DSIRE database (dsireusa.org) for your state.
State Incentives
VariesSome states have additional incentives on top of the federal credit. Massachusetts, New York, California, and several other states offer rebates of $500 to $3,000 for heat pump installations through state energy offices. Search "heat pump rebate [your state]" or visit dsireusa.org.
Common Questions
How long does central AC installation take?
Replacing an existing unit on existing ductwork typically takes 4 to 8 hours in a single day. A full new installation including ductwork can take 1 to 3 days depending on house size and how accessible the attic, crawlspace, or basement is.
Is a higher SEER rating worth the extra cost?
It depends on your climate. In hot climates where you cool 6 or more months a year, upgrading from SEER 14 to SEER 16 saves roughly $200 per year. Payback is 5 to 8 years. SEER 21+ units are most cost-effective in the South and Southwest for homeowners planning to stay 10 or more years.
Can I get a tax credit for a new AC system?
Yes. Heat pumps qualify for the federal 25C credit at 30%, up to $2,000 per year. Standard central AC units may qualify for up to $600 if they meet efficiency minimums. Check EnergyStar.gov for the current qualifying product list before you buy.
What size AC system do I need?
A rough rule is 1 ton of cooling per 400 to 600 square feet, but the accurate method is a Manual J load calculation. This accounts for insulation quality, window area, climate zone, and ceiling height. An oversized unit short-cycles and leaves your home humid even when it reaches the set temperature. Always ask your contractor to run a proper load calc before sizing a new unit.