Central Air Installation Cost Calculator
* Estimates for budgeting purposes. Includes equipment, labor, and refrigerant. Get professional quotes for exact pricing.
Disclaimer: Estimates are for budgeting purposes only. Actual costs vary by location, contractor, material availability, and project complexity. Always get professional quotes for exact pricing.
Central Air Cost by System Size
| System Size | Base Cost (14 SEER) | Home Size |
|---|---|---|
| 1.5 Ton | $3,000 – $5,000 | 600 – 900 sqft |
| 2 Ton | $3,500 – $5,500 | 900 – 1,200 sqft |
| 2.5 Ton | $4,000 – $6,500 | 1,200 – 1,500 sqft |
| 3 Ton | $4,500 – $7,500 | 1,500 – 1,800 sqft |
| 3.5 Ton | $5,000 – $8,500 | 1,800 – 2,100 sqft |
| 4–5 Ton | $5,500 – $10,000 | 2,100 – 3,000+ sqft |
* Base cost at 14 SEER includes equipment, labor, and refrigerant. Add $500–$4,000 for higher SEER ratings, $2,000–$6,000 for new ductwork.
How We Calculate
Our central air installation cost calculator estimates project costs based on system size (tonnage), SEER efficiency rating, and optional add-ons. Pricing includes equipment, labor, refrigerant, and standard installation.
How the math works: Unit cost = base price for selected tonnage + SEER rating premium. Ductwork = $2,000–$6,000 if included. Thermostat = $150–$500 if included. Total = unit cost + ductwork + thermostat.
System Sizing Guide
1.5 Ton ($3,000–$5,000): 18,000 BTU cooling capacity. Suitable for 600–900 sqft homes, apartments, or additions. Single-zone cooling. Lowest equipment and operating cost.
2–2.5 Ton ($3,500–$6,500): 24,000–30,000 BTU. Suitable for 900–1,500 sqft homes. Most common for smaller single-family homes and condos.
3 Ton ($4,500–$7,500): 36,000 BTU. The most popular residential size, suitable for 1,500–1,800 sqft average homes. Good balance of capacity and cost.
3.5 Ton ($5,000–$8,500): 42,000 BTU. For larger homes 1,800–2,100 sqft. Common in warmer climates where homes need extra cooling capacity.
4–5 Ton ($5,500–$10,000): 48,000–60,000 BTU. For large homes 2,100–3,000+ sqft. May require upgraded electrical panel and larger ductwork. Two-stage or variable-speed compressors common at this size.
SEER Rating Impact
14 SEER (base price): Minimum federal standard (15 SEER as of 2023 in southern states). Lowest purchase cost. Adequate for mild climates or budget installations. Single-stage compressor.
16 SEER (+$500–$1,000): 15–20% more efficient than 14 SEER. Two-stage compressor provides better comfort and humidity control. Popular mid-range choice. Payback period 5–8 years in warm climates.
18 SEER (+$1,000–$2,000): 25–30% more efficient than 14 SEER. Variable-speed or two-stage operation. Quieter, better dehumidification. Best value for hot climates (Southeast, Southwest). May qualify for utility rebates.
20+ SEER (+$2,000–$4,000): Maximum efficiency with variable-speed inverter technology. 35–40% energy savings over 14 SEER. Near-silent operation. Precise temperature control within 0.5°F. Premium brands (Carrier Infinity, Trane XV, Lennox XC). Best for homeowners planning to stay long-term.
Data Sources
Pricing from ACCA (Air Conditioning Contractors of America), HomeAdvisor, Angi, and manufacturer MSRP data. Efficiency ratings per AHRI (Air-Conditioning, Heating, and Refrigeration Institute) standards. We review and update regularly.
Last updated: 2026-02-11
Frequently Asked Questions
How much does central air installation cost? +
Central air conditioning installation costs $3,000–$10,000+ depending on system size and efficiency. A 1.5-ton unit for a small home costs $3,000–$5,000, a 3-ton unit for an average home $4,500–$7,500, and a 4–5 ton system for a large home $5,500–$10,000. Add $500–$4,000 for higher SEER ratings, $2,000–$6,000 for new ductwork, and $150–$500 for a smart thermostat. Total installed cost with all components typically runs $5,000–$15,000.
What size central AC do I need? +
Central AC sizing is based on home square footage and climate zone. General rule: 1 ton of cooling per 500–600 sqft in moderate climates. Small homes (600–900 sqft): 1.5 ton. Average homes (1,500–1,800 sqft): 3 ton. Large homes (2,100–3,000+ sqft): 4–5 ton. However, a proper Manual J load calculation by an HVAC contractor ($100–$300) is recommended — it accounts for insulation, windows, ceiling height, sun exposure, and climate zone for accurate sizing.
What SEER rating should I choose? +
SEER (Seasonal Energy Efficiency Ratio) measures cooling efficiency. Higher SEER = lower energy bills but higher upfront cost. 14 SEER (minimum legal): Lowest cost, adequate for mild climates. 16 SEER (+$500–$1,000): Good balance of cost and savings, reduces energy bills 15–20%. 18 SEER (+$1,000–$2,000): High efficiency, best for hot climates. 20+ SEER (+$2,000–$4,000): Maximum savings, variable-speed technology. In hot southern states, 16+ SEER typically pays for itself in 5–8 years through energy savings.
How long does central AC installation take? +
Standard central AC installation takes 1–3 days. If replacing an existing system with same-size unit and existing ductwork: 4–8 hours (1 day). New installation with no existing ductwork: 3–5 days. Adding ductwork to an existing home: 1–2 weeks. The installation process includes: removing old equipment, setting outdoor condenser pad, connecting refrigerant lines, electrical wiring, thermostat installation, testing and charging, and final inspection.
Should I replace my AC and furnace at the same time? +
Yes, replacing both together saves $500–$1,500 compared to separate installations because labor overlaps. Matched systems (same brand AC + furnace) operate more efficiently and qualify for full manufacturer warranties. If your furnace is 15+ years old, bundling makes financial sense. Average cost for AC + furnace combo: $6,000–$15,000 installed. HVAC contractors often offer package discounts of 10–15% for combo replacements.
How long does a central AC unit last? +
Central air conditioners last 15–20 years with proper maintenance. Factors that shorten lifespan: coastal salt air, oversized or undersized systems, poor maintenance, and extreme heat climates. Maintenance schedule: change filters monthly during cooling season, annual professional tune-up ($100–$200), keep outdoor unit clear of debris. Signs it's time to replace: frequent repairs exceeding $500, refrigerant leaks, R-22 Freon system (phased out), or unit is 15+ years old.
Do I need new ductwork for central air? +
New ductwork ($2,000–$6,000) is needed if: your home has no existing ducts (common in older homes with radiators), existing ducts are severely damaged or undersized, or you are significantly changing system capacity. Signs ductwork needs replacement: uneven room temperatures, excessive dust, visible damage, ducts over 15 years old, or high energy bills despite new equipment. Duct sealing and insulation ($1,000–$3,000) can improve existing ductwork without full replacement.
What are the annual operating costs for central AC? +
Annual central AC operating costs average $500–$1,500 depending on climate, system efficiency, and electricity rates. A 3-ton, 14 SEER unit in a hot climate costs roughly $800–$1,200/year. Upgrading to 16 SEER saves $120–$240/year, 18 SEER saves $200–$360/year. Average US electricity rate is $0.16/kWh. Programmable thermostats save 10–15% ($80–$180/year). Proper maintenance (clean filters, annual tune-up) can reduce costs 5–15%.
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