The lifespan of your air cleaner filters depends to a large extent on the air quality in the space where you use the air purifier, in average about 12 months. But for example, in an environment where will be smoked, the life span of the WINIX filters will be shorter. All WINIX air purifiers are equipped with an automatic filter replacement indicator so the device itself indicates when the filters of your WINIX air purifier needs to be replaced.