How Much Does It Cost to Run an Air Purifier in Montana? (2026)
Air purifiers run continuously at 10 to 100 watts depending on fan speed and room size. On a low setting they cost little; on high around the clock they can match a fridge.
A typical air purifier (40 W) costs $0.006 per hour, or about $4.36 per month at 24 hours a day in Montana. Average running cost
| Wattage | Per hour | Per day | Per month | Per year |
|---|---|---|---|---|
| Low 10 W | $0.002 | $0.036 | $1.09 | $13.26 |
| Typical 40 W | $0.006 | $0.15 | $4.36 | $53.05 |
| High 100 W | $0.015 | $0.36 | $10.90 | $132.63 |
Formula: watts ÷ 1000 × hours × price per kWh. Typical use is 24 h/day ≈ 350 kWh per year.
One day of an air purifier (0.96 kWh) is the same electricity as
- 5.3km in an electric car
- 9.6hours of TV
- 21hours of a laptop
- 107hours of an LED bulb
In Montana, with electricity at 15.1¢ per kWh (source: EIA Table 5.6.A, 2026-06), a typical air purifier costs $0.006 per hour and about $53.05 per year at 24 hours a day. That is about 17% less than the national average for the US ($5.28 per month), because electricity in Montana costs 15.1¢ per kWh against 18.3¢ nationally. Each $1.00 of electricity buys roughly 165.1 hours of use.
How to lower the cost of running an air purifier
- Run on high only to clear a room, then drop to low or auto.
- Replace filters on schedule. A clogged filter makes the fan draw more for less air.
- Size the unit to the room. An oversized purifier on low beats a small one on high.
In standby it draws about 1 W, which adds roughly 9 kWh ($1.33) per year if it is never unplugged.
Frequently asked questions
How much does it cost to run an air purifier 24/7?
About 29 kWh a month at 40 watts. Pick your region above.
Do air purifiers use a lot of electricity?
Not per hour, but continuous use adds up. Auto mode helps.
Should I leave my air purifier on all the time?
Manufacturers say yes for consistent air quality. On low, the cost is small.
Cost by region
US states
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Canadian provinces
Related appliances
- Electric Blanket100 W typical
- Heat Pump (Ducted or Mini-Split)2,000 W typical
- Baseboard Heater1,500 W typical
- Portable Fan (Box or Pedestal)50 W typical
Use the generic electricity cost calculator · Which uses more? Take the quiz