Most homeowners pay about $4,000 to $9,000 to install central air when ductwork already exists, and $8,000 to $15,000 when ducts have to be added. A standard 3-ton system for a roughly 2,000 sq ft home usually lands between $5,500 and $8,500 installed.
Published cost guides disagree by a few thousand dollars, because they sample different regions and contractors. The ranges below are the zone where most of them overlap, so treat them as a budgeting range and confirm with local quotes.
Central air installation cost by home size
The size of your home sets the tonnage you need, and tonnage is the biggest equipment cost. These are installed prices (equipment, labor and basic permits):
| Home size | System size | Existing ducts | New ducts needed |
|---|---|---|---|
| 600–1,000 sq ft | 1.5 ton | $2,500–$4,500 | $6,000–$9,500 |
| 1,000–1,500 sq ft | 2 ton | $3,200–$5,500 | $7,000–$11,500 |
| 1,500–2,000 sq ft | 2.5–3 ton | $4,000–$7,500 | $8,500–$13,000 |
| 2,000–2,500 sq ft | 3–3.5 ton | $4,800–$9,000 | $9,500–$15,000 |
| 2,500–3,000 sq ft | 4 ton | $6,000–$11,000 | $11,000–$18,000 |
What drives the price of a new AC system
Tonnage. One ton of cooling covers roughly 400 to 600 sq ft depending on climate, insulation and sun exposure. The equipment alone runs from about $1,900 for a small unit to $5,000 or more for a large one.
Efficiency (SEER2). Federal minimums are 13.4 SEER2 in the northern states and 14.3 SEER2 in the south. Stepping up to a 16+ SEER2 unit typically adds $800 to $2,500 in equipment cost, and pays back through lower summer bills, faster in hot climates.
Ductwork. This is the swing factor. Sound existing ducts keep the job to equipment plus labor. New or heavily repaired ducts can add $3,000 to $10,000 or more and turn a one-day swap into a multi-day project.
Labor and permits. Installation labor commonly runs $1,000 to $4,500 and permits $100 to $500 or more, depending on your city. Metro areas with high labor rates sit toward the top of every range.
Refrigerant and equipment generation. New systems now use lower-impact refrigerants instead of R-410A, which has nudged equipment prices up. Ask your installer which refrigerant the quote assumes.
How to size a central air system correctly
A bigger unit is not a better unit. An oversized AC cools the house in short bursts, never removes enough humidity and wears out early. An undersized one runs constantly and never catches up.
Ask every contractor for a Manual J load calculation before you sign. It accounts for your insulation, windows, ceiling height and climate, and it is the industry standard for sizing. A quote that sizes the unit only by square footage is a warning sign.
Is there a federal tax credit for a new AC in 2026?
No. The federal Energy Efficient Home Improvement Credit (Section 25C) ended for equipment placed in service after December 31, 2025, so it does not apply to a system you install this year. Check your state energy office and your electric utility, because local rebates for high-efficiency equipment still exist in many areas.
How to save on central air installation
1. Get three written quotes from licensed, insured contractors. Prices for the same job often differ by $1,000 or more.
2. Compare the same specs. Match tonnage, SEER2 rating, brand tier, warranty length and what is included (permit, haul-away, thermostat).
3. Schedule outside peak season. Spring and fall installs are often easier to negotiate than a mid-summer emergency.
4. Replace the furnace at the same time if it is also near the end of its life. Many contractors discount a bundled system. See our furnace replacement cost calculator to budget the heating side.
5. Ask about utility rebates before choosing an efficiency tier.