AC Installation Cost in Montana

Across Montana, homeowners pay $3,800 to $8,500 for new AC installation. Climate, labor rates and housing age all move the price. In Montana's cities, the median home dates to about 1978.

AC Installation Prices in Montana Cities

City	Estimate	Heating / cooling degree days
Billings	$3,800 to $8,700	6,753 / 662
Missoula	$3,800 to $8,700	7,182 / 340
Great Falls	$3,500 to $7,900	6,942 / 421
Bozeman	$4,300 to $9,800	7,827 / 229
Butte	$3,300 to $7,600	9,128 / 82

From 2020 through 2025, NOAA recorded 1,442 winter storm and ice events, 13 heat events, 471 extreme cold events and 905 hail reports in Montana. Those are the days when emergency HVAC calls pile up.

When It Makes Sense

The AC is 12 to 15 years old or more
It still runs on R-22 refrigerant
It has had more than one refrigerant leak
The house can't reach the thermostat setting on hot afternoons
Summer electric bills keep going up

What Moves the Price

Tonnage, based on house size and local climate
SEER2 rating and whether the compressor is single-stage or variable-speed
Whether the coil and line set also need replacing
Electrical work such as a new disconnect, breaker or wiring
The pad, permit and refrigerant (R-410A or the newer R-454B)

Common Questions

What size AC do I need?

It depends on square footage, insulation, windows and climate. The rough rule is a ton for every 450 to 650 sq ft, but only a Manual J calculation gives you a real number.

How long does a new AC last?

With yearly maintenance, 12 to 17 years. Salt air and extreme heat shorten that.

Other HVAC Prices in Montana

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