Filtrete 21x21x1 Air Filter – MERV 11, MPR 1000, 6-Pack, 3-Month Replacement (Actual Size 20.81 x 20.81 x 0.81 in)

Cleaner air for everyday life

The Filtrete 21x21x1 air filter set brings three-month protection to your home HVAC system with a powerful blend of filtration and airflow. Manufactured by 3M, this six-pack is designed for standard 21x21x1 intakes and includes filters with a 1000 MPR rating and a MERV 11 efficiency level. These filters are built to reduce the amount of fine particles that circulate through your rooms, while still allowing your furnace or air conditioner to run efficiently.

How it works

Designed with Filtrete 3-in-1 technology, these pleated filters pull in and trap a range of particles so cleaner air can pass through. The combination of high MPR 1000 and MERV 11 means the filter captures many microparticles and larger debris alike, helping keep your indoor air flow steady without overly restricting your HVAC system.

• Microparticle capture: Targets particles in the 0.3 – 1.0 micron range while maintaining airflow.
• Broad debris filtration: Traps lint, pollen, dust, pet dander, and typical household particulates.

What you can expect

While not a medical claim, many users notice a fresher, cleaner feel in rooms that rely on central heating and cooling. The filter’s mix of particle capture and airflow support can contribute to a consistently comfortable environment, especially in homes with pets, smokers, or seasonal pollen surges.

• Asthma and allergy-conscious certification
• Ease of replacement with standard 20.81 x 20.81 x 0.81 inch actual size
• 6-pack for multi-month convenience and predictable maintenance

Smart maintenance, simple reminders

Stay on top of replacement with the Filtrete Smart App. Scan the filter packaging barcode to set a 30-, 60-, or 90-day countdown. When the filter life is up, you’ll receive a notification—helping you maintain ideal airflow and consistent performance.

What’s in the box and where to use it

This is a six-filter pack, intended for use in furnaces, air conditioners, or HVAC systems that accommodate 21x21x1-inch filters. For optimal results, replace each filter at least every 90 days, depending on usage and air quality. The actual size is 20.81 x 20.81 x 0.81 inches, ensuring a snug fit in many standard housings.

• 6 pleated filters per pack
• Actual size: 20.81 x 20.81 x 0.81 in
• Suitable for most 21x21x1 furnace or AC filters