The Bionaire HWF100, which is identical to the BWF100, is the cheapest replacement filter available from Bionaire, at a mere $5.99. It is intended to fit Bionaire humidifiers, and has Microban antimicrobial properties.

The other filters that Bionaire offers are not much more expensive, with most of them coming to around $7.50 from the Bionaire website. Because of this, it may be wise to investigate the specific features and make a decision based on that rather than price.

The cheapest Bionaire Humidifier filter is the HWF100, which costs $5.99. However, as the other filters are not much more expensive, you may want to choose which one you want based on features rather than cost.

Source:

Guys who know about ductless split system repair.