A good box fan lasts 5-10 years.

A quality box fan typically lasts 5 to 10 years, but that depends on how often you run it and whether you clean it.

The main killers are dust buildup and cheap motors. If you run a box fan 24/7 all summer, you’ll get closer to the low end. If you store it off-season and wipe the blades and grille every month, you might hit the top end. Brands like Lasko, Vornado, and Air King tend to hold up better than the no-name ones.

Most modern box fans have sealed bearings, so when the motor starts humming or barely spinning, it’s usually done. You can sometimes oil a sleeve bearing motor if the fan has oil ports, but that’s rare on newer models. Really cheap ones (under $20) often die before year three.

Don’t expect a miracle from a $15 fan.