The Filterbuy MERV 8 is a 1-inch deep pleated filter. The 20″x25″x1 version we tested contained 21 pleats. While this type of filter will fit most filter slots and housings, its performance is far from exceptional.

Rated at a Filtest permeability score of 6.48 (higher means better), the FilterBuy MERV 8 furnace filter pressure-delta is considered high. A higher pressure delta would put more strain on your furnace (or AC) blower fan, which would lead to higher consumption of energy and would potentially shorten the life of your equipment when compared to filters with a higher permeability score.

As with other filters in the 1-inch deep category, this filter requires frequent replacements (which we are not big fans of).

As for the FilterBuy MERV 8 filter’s filtration performance, its sub-micron performance is terrible (4.9% @ 0.3-1µm) and quite bad at the 1-3µm level (38.4%). The performance of this filter at the 3-10µm level is a C- (72.2%), however, Fltest.org does not incorporate this category into the weight of our scores.