Box Fan Wattage Revealed [Data + Most Efficient Box Fan]

How many watts does a box fan use? See the average & get a breakdown of wattage based on size. Also, get the wattage of over 40 of the most popular and efficient box fans.

Box fans are some of the most efficient appliances for cooling. But how efficient are they and which is the most efficient? I’ve researched the wattage of close to 100 of the most sold box fans in the US. Here are the results.

On average, box fans use 73W of electricity at full speed. Smaller box fans use 27W, while 20 inch box fans consume 86.5W on average.

The watts consumed reduces at lower speeds. Continue reading to see how much watts are used at lower speeds and get details about the most popular and most efficient box fans on the market today.

Box fan wattage image of fan grill | Eco Cost Savings

If you’re interested in the running costs, check out my recent post: Cost To Run A Box Fan.

How many watts does a box fan use?

The wattage of box fans varies considerably. Larger box fans operating at full speed consume substantially more watts than smaller box fans. 

For this reason, I have focused the research on the most popular box fan sizes and broken the results down into 3 categories: overall results, results for 20” box fans and results for box fans that are 10” or less.

The wattage for specific box fan sizes and models are detailed below. 

But first, let’s look at the overall results.

Overall, regardless of size, box fans use 73W on average at full speed. This drops to approx. 47.3W at the lowest speed setting and 59.5W at medium speed. 

The most common box fan power rating identified in the research was 100W. 5W was the lowest recorded wattage, while 220W was the highest.

On average, based on research into actual power consumption at different speeds, box fans use 64.84% of its power rating at its lowest speed setting and 81.53% at its medium speed setting, if available. 

The most common size box fan recorded was 20 inches. These fans use more watts than average due to their size. So let’s look at results for these in isolation.

How many watts does a 20 inch box fan use?

On average, 20 inch box fans use 86.5W at full speed. At lowest and medium speeds, 20 inch box fans use approx. 56W and 70.5W respectively.

The lowest recorded wattage in the research was Genesis’ 20″ Box Fan at 53W. The highest recorded wattage was 220W.

The most common power rating for 20 inch box fans is 100W.

The average CFM (this stands for cubic feet per minute and refers to how much air a fan moves) recorded was 1,750. This is a crucial consideration when choosing an energy efficient box fan.

Most efficient box fan and editor’s choice

At 60W and with a CFM of 2,294, the Brentwood 20 in. 3-Speed Box Fan appears to be the most efficient box fan. 

However, given lower watts used, the ratings, reviews, features and value for money, I’d recommend the Genesis Box Fan. Despite its very low power consumption (the lowest 20 inch box fan wattage recorded) it still achieves an above average CFM of 1,800 – more than enough for the vast majority of people.

Also, it’s very competitively priced – check out the current price on Amazon, here.

How many watts does a small box fan use?

Based on research into nearly 100 of the most popular box fans, smaller box fans (i.e. those less than or equal to 10 inches) use 27W on average.

The lowest recorded wattage for small box fans was 5W, while the highest was 45W.

Interestingly, the lowest wattage box fan recorded is slightly lower than the lowest recorded tower fan wattage (6W). For more details, check out the Tower Fan vs Box Fan section, here.

To see how box fans compare with ceiling fans, don’t miss the Ceiling Fan vs Box Fan section, here.

Related post: Fan Wattage, Efficiency And Cost To Run [Fan Types Compared].

Reduce electricity costs and carbon footprint

Cooling households accounts for a substantial amount of electricity consumption in the US.

EIA notes that “the residential sector’s electricity use for cooling was about 226 billion kWh in 2019, which was equal to about 16% of total residential sector electricity consumption and 6% of total U.S. electricity consumption.”

226 billion kWh is equivalent to running 41 coal-fired power plants, yearly.

The use of box fans is one of the more efficient modes of cooling. Choosing to run a box fan instead of your AC will save you money while also reducing your carbon footprint.

To reduce your electricity costs even more, consider using smaller box fans or more efficient models. Check out my recent post to see the electrcity cost of box fans and get 6 easy tips to reduce your costs and carbon footprint.

If you’re looking to buy a box fan consider the CFM and power consumption along with your specific requirements. 

I’ll be going with the Genesis Box Fan for my next box fan purchase as it suits my needs – cheap to run, has a lower environmental impact, it’s efficient, feature rich and has a good CFM.

For convenience, I’ve listed the wattage, CFM and links for a number of box fans below. I hope it’s useful on your hunt for an efficient box fan.

Wattage of the current (as of writing) most popular box fans on Amazon

Box FanWatts
1Lasko #B20301 20-Inch Premium Box Fan 3-SPEED110W
2AC Infinity AXIAL 123818W
3Comfort Zone CZ9BWT30W
4Comfort Zone CZ200A 20″ 3-Speed Box Fan75W
5Lasko FF305 20-inch Box Fan and Air Purifier120W
6Holmes HBF2010AWM 20″ White100W
7Holmes HBF2001DP-BM 20-Inch Box Fan100W
8Lasko 20″ Weather-Shield Performance Box Fan112W
9Optimus F-102225W
10LASKO 20 inch Box Fan55W
11Lasko 3733 20″ Fan Box92W
12Polar-Aire S-9PB Mini Box Fan, 9″29W
13Lasko 3721 20 inch Power Plus Box Fan102W
14Genesis 20″ Box Fan53W
15Amazon Basics DK1901 3 Speed Box Fan, 20-Inch67W
16Lasko 20 Inch Box Fan55W
17Camair Bx100 High Performance Box Fan68W
18OPOLAR 8 Inch Fan5W
19Best Comfort 20″ Box Fan
20Lasko B20500 Weathershield Performance Box Fan, 20-Inch90W
21SOFASCO Cooling fan sA12038V1HSL-C32W
22CCC COMFORT ZONE 9 Inch Portable Box Fan, 9″24W
23HOLMES HBF2010AWM 20″ White 3 Speed Box Fan100W
24Lasko B20725 Metal Box Fan, 20-Inch100W
25Lasko 3743 Weather Shield Premium Plus Box Fan, 20-Inch90W
26Comfort Zone CZ10B – 10″ Portable Box Fan38W
27Brentwood Kool Zone Oscillating Fan, 30-inch100W
28Comfort Zone 20″ High Velocity Turbo Fan65W
29Uniware 8062 20 Inch Box Fan82W
30Lasko B20401 Decor Colors 20″ Box Fan55W

See the up to date best sellers on Amazon, here.

Wattage and CFM of the most sold box fans on Home Depot

Box FanWattsCFM
1Lasko 20 in. Box Fan55W1,820
2Lasko 20 in. 3-Speed Box Fan75W1,820
3Lasko 20 in. Power Plus Box Fan111W2,000
4Lasko 20 in. 3-Speed Weather Shield Performance Box Fan90W2,095
5Comfort Zone 9 in. White Box Fan with 2-Speed Front Control25W153
6Comfort Zone 20 in. White High Performance Box Fan with Carry Handle75W640
7Comfort Zone 20 in. High Performance Box Fan with Carry Handle in Black220W640
8Brentwood 20 in. 3-Speed Box Fan60W2,294
9Brentwood 20 in. Black Box Fan60W
10Impress 9 in. White Box Fan45W
11Lasko Weather-Shield Select 20 in. 3-Speed Box Fan with Thermostat100W2,195
12Lasko Premium 20 in. 3-Speed Box Fan102W2,091
13GENESIS 20 in. Black 3-Speed Settings Box Fan with Max Cooling Technology53W1,800
14Optimus 20-in. 3 Speed Box Fan75W1,850

Data source

While these tables don’t reflect the whole data set, I hope they are of some help with your mission to keep cool, efficiently.

Speaking of keeping cool, do you know how much it costs to run your refrigerator? Your fridge runs 24 hours a day, 365 days per year – you might be surprised by the electricity costs. Check out the cost of running a refrigerator and get 9 simple cost saving tips.

But what about the cost of running a box fan? See the hourly, daily, weekly & monthly cost to run a box fan here. There’s a useful calculator that can help you work out your own box fan running costs and also included are 6 easy tips to reduce your costs & your carbon footprint.