Shop Furnace and AC Filters - Trusted in Filtration Since 2006

Over a million filters sold and replaced. That’s billions of particles removed from indoor air. Trust your air to us. RTF has been in business for 15+ years and is a preferred online retailer for AAF Flanders Furnace and AC Filters. We sell filters by the case or individual filters with our subscription program.

Quality Furnace and AC Filters Online

What’s your need? Commercial? Residential? Industrial? HEPA? We have you covered! At RememberTheFilter.com, you’ll find the perfect HVAC filter online for your system. Our stock features leading manufacturers!

Buying furnace and AC filters online at RememberTheFilter.com is easy, convenient, and saves you time and money. No high-pressure sales. No time-consuming service appointments. No searching for weeks or months for your filter size. Just friendly, knowledgeable filter experts dedicated to helping you select the right filters for your system.

With thousands of sizes to choose from, you’ll never have to search for your filter again! You can even buy custom furnace and AC filters online! We’ll send you perfect fit filters for your HVAC system. We deliver filters to you for free, too! Whether you live here with us in the Pacific Northwest, or you’re in Texas, Chicago, New York, Los Angeles, or Florida, we deliver for free anywhere in the entire contiguous United States – even oversized or special order filters.

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Different HVAC Ratings Explained

Different HVAC Ratings Explained

The sequences of letters and numbers in the HVAC world can be difficult to decipher. Learn their meanings in this guide to HVAC rating systems.
Common Causes of an AC Freezing

Common Causes of an AC Freezing

Has your air conditioning unit become ensconced in a block of ice? Here’s why your AC unit freezes up and how you can prevent it from doing so in the future.
HEPA vs. MERV Filters: The Differences

HEPA vs. MERV Filters: The Differences

High-efficiency particulate air and minimum efficiency reporting value filters—they sound complicated, but they’re simpler than you think. Learn more here.