AC Replacement Cost Calculator
Size first, brand later. The size of the system sets most of the AC replacement cost, so the calculator starts by asking for it, then multiplies by an installed price per ton for the system type and efficiency you choose. For a sense of scale, Fixr puts the average job at $8,750 (most fall between $5,800 and $14,400), and Trane’s own pricing guide runs from $6,568 to $13,669 depending on the compressor.
Find your tonnage before you get quotes
The outdoor unit’s model number usually contains the size in thousands of BTU: 24, 30, 36, 42, 48 or 60 mean 2, 2.5, 3, 3.5, 4 or 5 tons. If the old unit kept the house comfortable, the same size is a sensible starting point.
Without that, Trane’s sizing chart works out to about one ton per 600 sq ft: 2 tons for 1,200 sq ft, 3 tons for 1,800 and 5 tons for 3,000. Trane notes that older, leakier houses may need a ton per 400 sq ft and new, tight ones as little as a ton per 1,000. Carrier’s guide matches a 3-ton unit to homes of 1,500 to 2,000 sq ft. A contractor’s load calculation settles it.
AC replacement cost by unit size
Fixr’s installed prices for a central air replacement, which make up most of the AC unit replacement cost:
| Size | Installed cost |
|---|---|
| 2 ton | $4,250 to $7,500 |
| 2.5 ton | $4,500 to $8,000 |
| 3 ton | $5,000 to $9,150 |
| 3.5 ton | $5,450 to $9,700 |
| 4 ton | $6,950 to $11,600 |
| 5 ton | $7,800 to $14,000 |
Doubling the size does not double the price, because much of the labor and many parts cost the same at any size.
What higher efficiency adds
The federal minimum is 13.4 SEER2 in northern states and 14.3 SEER2 in the Southeast and Southwest, so the “standard” option is a current-code unit. Every source we checked charges more for the better tiers:
- Trane, installed: $6,568 to $8,544 for single-stage, $8,573 to $10,671 for multi-speed, $11,525 to $13,669 for variable speed.
- PickHVAC, a typical 3-ton job: $5,100 at 14 SEER, $6,600 at 16 and $8,100 at 18.
- Fixr, the cost of a new AC unit before installation: $1,725 to $3,600 at 13.4 SEER2, $5,750 to $9,600 at 19.1 SEER2.
The calculator adds about 27% for the mid tier and 70% for the high tier, the middle of those jumps.
AC, heat pump, or a full HVAC system replacement?
A heat pump instead
It cools and heats. Per ton it runs roughly a quarter above an AC alone: Fixr lists a 2-ton model at $5,000 to $8,000 installed against $4,250 to $7,500 for a 2-ton central AC.
Furnace and AC together
Swapping the furnace on the same visit turns the job into an HVAC system replacement cost. Fixr prices a furnace alone at $2,000 to $11,000, and puts the pair at $7,500 to $21,000; PickHVAC gives $7,100 to $22,000. No source we could open breaks the combined job down by tonnage, so the calculator adds the furnace as its own line.
Checklist for the rest of the quote
| Line on the quote | Typical cost | Source |
|---|---|---|
| New refrigerant line set | $370 to $795 | PickHVAC |
| Ductwork replaced with the system | $1,400 to $6,000 | Fixr |
| Permit and inspection | $100 to $800 (Fixr $50 to $1,500; Today’s Homeowner $250 to $750 plus inspection) | Fixr, Today’s Homeowner |
| New disconnect or circuit | $300 to $2,000 | PickHVAC, Today’s Homeowner |
| Removing the old unit | usually included, otherwise $150 to $250 | Fixr |
Whole-house duct replacement is a bigger job: Fixr’s ductwork guide runs from about $1,400 to over $17,000.
Where the sources disagree
Fixr’s two AC pages do not match. The 2026 page puts the low end at each tonnage at about half of the 2025 table used above, which agrees with Today’s Homeowner. We use the 2025 figures.
AC replacement cost per ton by system type
| System type | Low | High |
|---|---|---|
| Central AC (outdoor unit + coil) | $1,600.00 | $3,200.00 |
| Ducted air-source heat pump | $2,300.00 | $4,000.00 |