AC & Heat Pump Cost by Size: 2 to 5 Ton Installed Prices in Phoenix (2026)
What a 2, 2.5, 3, 3.5, 4 and 5 ton AC or heat pump costs installed in Phoenix and the East Valley in 2026, split vs. rooftop, what each half ton adds, and how to tell what size your house actually needs.
"How much is a 3.5 ton heat pump?" and "how much is a 5 ton AC unit?" are some of the most common questions we see from Phoenix homeowners. Size is the biggest single driver of the price, so here are 2026 installed numbers for every common size, side by side.
These are market ranges for the Valley, not our price list. Our number is a written quote after we've measured the house.
Installed price by size: split-system AC
Outdoor condenser plus matched indoor coil or air handler.
| 2 to 2.5 ton | $6,000 to $9,000 | Condos, casitas, small single story |
| 3 to 3.5 ton | $7,000 to $11,500 | 1,400 to 1,800 sq ft, the most common size |
| 4 ton | $8,000 to $13,000 | 1,800 to 2,200 sq ft |
| 5 ton | $9,000 to $15,000 | Large single story, or one of two systems |
Installed price by size: split-system heat pump
Same layout, but the outdoor unit also heats in winter. Most Valley homes built since the '90s have one.
| 2 to 2.5 ton | $6,000 to $9,500 |
| 3 to 3.5 ton | $7,000 to $12,000 |
| 4 ton | $8,000 to $13,500 |
| 5 ton | $9,000 to $15,000 |
Installed price by size: rooftop package unit
Everything in one box on the roof. Includes the crane, which most rooftop jobs need.
| 2 to 2.5 ton | $6,500 to $9,500 |
| 3 to 3.5 ton | $7,500 to $12,000 |
| 4 ton | $8,500 to $13,500 |
| 5 ton | $9,500 to $15,500 |
All three tables run from a value-tier 14.3 SEER2 system to a mid-tier 15.2 to 16 SEER2 system with a 10-year registered parts warranty. Two-stage adds roughly $1,500 to $3,500, and variable-speed adds roughly $3,500 to $7,000. More detail: split-system cost, heat pump cost, rooftop package unit cost.
What each extra half ton adds
Going up a half ton usually adds $500 to $1,000 to the installed price. The labor, permit, crane and thermostat cost about the same whether the unit is 3 or 4 ton. Equipment is what scales. That's why a 5 ton isn't twice the price of a 2.5 ton.
The catch: 5 ton is the biggest single residential system made. A house that needs more than that gets two systems, and the price roughly doubles.
How to tell what size you have
Look at the model number on the outdoor unit's data plate. Somewhere in it is a number divisible by 6: 24 is 2 ton, 30 is 2.5, 36 is 3, 42 is 3.5, 48 is 4, 60 is 5. That number is thousands of BTUs; 12,000 BTU is one ton.
How to tell what size you need
The rule of thumb in Phoenix is roughly one ton per 400 to 550 square feet, so a 1,800 sq ft house lands around 3.5 to 4 ton. But that's a starting point, not an answer. What actually sets it:
- West-facing glass and single-pane windows
- Attic insulation (many 1980s Valley homes have half what they should)
- Duct leakage, especially in a 150° attic
- Ceiling height, additions, converted garages
- How many people are home in the afternoon
A real bid comes with a load calculation (Manual J), not just "same size as the old one." A lot of Valley homes were oversized from day one. An oversized system cools fast, shuts off, and never runs long enough to pull humidity out in monsoon season. It also wears out sooner from short cycling. Sometimes the right answer is a half ton smaller, which saves money twice.
Bigger isn't cooler
When a house won't hold 78° in July, the instinct is to buy more tonnage. Usually the problem is airflow or ducts, not size. A 4 ton on ducts built for 3 ton just gets loud and freezes coils. Check the ducts first; our ductwork cost guide covers what that runs.
Rebates scale with size too
SRP Cool Cash pays per ton on 15.2+ SEER2 systems: $75 per ton single-stage, $150 two-stage, $225 variable-speed. On a 4 ton variable-speed system that's $900 back. APS has no equipment rebate in 2026. Full rebate breakdown.
Questions people ask
How much is a 3.5 ton heat pump installed in Phoenix?+
Most 3 to 3.5 ton split heat pumps run $7,000 to $12,000 installed in 2026, from a value 14.3 SEER2 unit to a mid-tier 16 SEER2 system. Two-stage and variable-speed cost more.
How much is a 5 ton AC unit installed?+
Usually $9,000 to $15,000 installed in the Valley for a split system, and $9,500 to $15,500 for a rooftop package unit, before premium efficiency tiers.
How many square feet does a 3 ton AC cool in Phoenix?+
Roughly 1,200 to 1,650 square feet by rule of thumb, but insulation, windows and ducts move that a lot. A load calculation is the only real answer.
Is it worth going up a size?+
Usually not. An oversized system short-cycles, controls humidity poorly and wears out sooner. Size to the load calculation, and fix ducts before adding tonnage.
Why does the price per ton go down as units get bigger?+
Labor, permit, crane and thermostat cost about the same on every size. Only the equipment scales, so each extra half ton adds roughly $500 to $1,000.