Editor's pick
WindowENERGY STAR
LG Dual Inverter LW1022IVSM
Cooling
10,000 BTU
Covers
450 ft²
Efficiency
15 CEER
Noise
44 dB
$429 est.
typical retail price Mixed / Temperate · ~29¢/kWh · 4-month season
Air conditioning in Massachusetts: sizing, costs & the right units
Massachusetts summers turn hot and humid across Greater Boston and the Connecticut River Valley, with coastal moisture and urban heat islands pushing July–August comfort over the edge. The Berkshires stay cooler, but the populous east carries a real, if short, cooling season.
Updated June 2026
What to look for in Massachusetts
Massachusetts has some of the highest power rates in the country, so efficiency is a genuine budget lever — an inverter unit that sips power pays back faster here than almost anywhere. Older Boston triple-deckers often cap window circuits at 15 amps, so check before a 14K+ unit, and prioritize dehumidification for the coastal mugginess.
What cooling costs in Massachusetts
Estimated at Massachusetts's average residential rate (~29¢/kWh, approximate) and 8 hours/day. "Per season" assumes 4 cooling months. Your utility rate and usage will vary.
| Unit | Efficiency | Est. / month | Est. / season |
|---|---|---|---|
| Senville LETO SENL-12CD Mini-split | 21.2 SEER2 | $45 | $180 |
| LG Dual Inverter LW1022IVSM Window | 15 CEER | $46 | $184 |
| BLACK+DECKER BPACT14WT Portable | 6.1 CEER | $160 | $640 |
Climate-matched
All 49 units Units that fit Massachusetts's climate
Mini-splitENERGY STAR
Bosch Climate 5000 12K
Cooling
12,000 BTU
Covers
600 ft²
Efficiency
22 SEER
Noise
20 dB
$1299 est.
typical retail price
WindowENERGY STAR
Midea Smart MAW08HV1CWT
Cooling
8,000 BTU
Covers
350 ft²
Efficiency
14.5 CEER
Noise
50 dB
$379 est.
typical retail priceMassachusetts AC questions, answered
How many BTU do I need in Massachusetts?
Use the Mixed/Temperate zone. A 300 ft² room sizes to about 6,500–7,500 BTU; humid coastal and Boston rooms favor the upper end.
What type of AC works best in Massachusetts?
A high-efficiency inverter unit. With Massachusetts' steep rates, the efficiency premium pays for itself fast, and inverter drive dehumidifies the coastal air better than a fixed-speed unit.
What does AC cost to run in Massachusetts?
At ~29¢/kWh — among the nation's highest — an efficient 12,000 BTU unit runs about $48–60/month at 8 hours a day, while an old fixed-speed unit can push past $90. Efficiency matters more here than the short season suggests.
Electricity rates are approximate state averages; check your utility bill for your exact rate.