Furnace filters are designed to trap harmful pollutants and particles that residents may inhale while spending time in the home. Each filter has a specific MERV rating, which determines how much dirt, grime, and smoke it can trap when the furnace is in use. We reviewed many different furnace filters that measure 16x20x1 to determine which products were most effective and delivered the best results. Check our best 16x20x1 furnace filters in 2021 picks down below!