Lennox replacement air filters

Caliper makes replacement air filters that fit Lennox furnaces, air handlers and AC systems. What matters is the size of your filter slot, not the brand on the unit, so you'll get an exact fit either way.

Find your size

The quickest way: check the edge of the filter that's in there now. The size is printed on the frame, like 16x25x1. You can also take a photo of your old filter, or of the label on your Lennox unit, on our home page and we'll read it for you.

Where the filter lives

On most Lennox systems, the filter sits in a slot next to the blower, in a wall or ceiling return grille, or in a separate filter cabinet. Cabinets usually take thicker 4" or 5" filters, which last longer.

Common sizes in homes

Don't see yours? See every size, or order a custom size.

Caliper isn't affiliated with or endorsed by Lennox. We use the name only to help you find a filter that fits your equipment.