Frequently Asked Questions

To determine the size you need, check the existing filter in your unit. Look for the nominal size, usually in large print, and the actual size in small print on the frame. If you can’t find the size, use a tape measure to measure the length, width, and depth.

MERV (Minimum Efficiency Reporting Value) rates air filter effectiveness. Higher ratings indicate greater particle-trapping efficiency. Explore our MERV 8, 11, 13 and Carbon filters designed for different needs.

Furnace filters and AC filters are interchangeable terms for the same product, serving HVAC systems.

Pleated filters should be replaced every 90 days or more frequently if you have pets, children, or allergy sufferers. Regular replacements enhance air quality and HVAC performance.

Filter King pleated filters outperform fiberglass filters in both durability and particle-capturing efficiency. While fiberglass filters are economical and typically last around 30 days, Filter King pleated filters feature advanced pleating technology and superior materials, providing extended durability and capturing a wider range of airborne particles. Pleated filters are an optimal choice for maintaining cleaner indoor air over an extended period, making them a cost-effective solution for homeowners seeking improved air quality and convenience.

We offer free shipping within the continental US for any order over $50 and accept returns within 90 days for any standard filter. Contact us for assistance with returns. Please be aware custom filters are not returnable.

Track your order via the shipping confirmation email, signing in your Filter King account or just give us a call.

You can enjoy 5% off by signing up for a subscription!

Changing your air filter is a breeze! Ensure you have the correct size, turn off the power supply, remove the old filter, insert the new filter with arrows pointing in the airflow direction, and replace the cover.

Nominal size, printed prominently, is the rounded-up actual size of the filter.

Arrows on the filter frame indicate airflow direction. For assistance, call us at (877) 570-9755.

Yes, our filters are electrostatically charged for enhanced particle attraction.

Air filters trap various particles, including dust, dirt, pollen, and mold spores. MERV ratings determine filtration efficiency.

Our subscription service ensures timely filter replacements. Choose your delivery frequency, and we’ll handle the rest. Learn more about recurring orders here or call us at (877) 570-9755 for assistance.

Yes, we offer wholesale options for bulk purchases. Contact us here for wholesale inquiries.