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Actual Size: 13x21x1"
3 month filters
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Made in the USA
Ships in 24 hours
Available In MERV Rating: 8, 11, 13
Made in the USA
Ships in 24 hours
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 MERV 8 |  MERV 11 |  MERV 13 | |
|---|---|---|---|
| Best for | Standard Residential/Commercial Healthy Families | Superior Residential/Commercial Allergy Sufferers | Optimal Residential/Commercial Hospital Grade |
| Comparable ratings | MPR 600 & FPR 5 | MPR 1000-1200 & FPR 7 | MPR 1500 - 1900 & FPR 10 |
| Filtration | Captures 90% of Airborne Particles | Captures 95% of Airborne Particles | Captures 98% of Airborne Particles |
| Dust, lint & debris | |||
| Mold, pollen | |||
| Dander, dust mites | |||
| Smoke & Smog | |||
| Bacteria | |||
| Odor, vocs |
Generally, we recommend you replace your air filters every 90 days. Find out below if you should change your filters more often.
Change your filter every
6 weeks
to ensure indoor air quality is at its best.
Change your filter every
2 months
to avoid shedding and odor buildup.
Change your filter every
2-3 months
as having clean air is even more important with children in your home.
Change your filter every
6 weeks
to ensure indoor air quality is at its best.
Change your filter every
2 months
to avoid shedding and odor buildup.
Change your filter every
2-3 months
as having clean air is even more important with children in your home.
The air inside your home affects your family's health and comfort. A clean indoor environment is more important than ever. Your air filter is your first line of defense. It captures dust, allergens and other airborne particles before you breathe them in.
Discover how upgrading to Filterbuy 13x21x1 air conditioner filter can make a difference in your home's air quality.
Filterbuy 13x21x1 air filters help block allergens and boost air quality.
Filterbuy filters are high-performance and USA made.
Families notice better breathing and cleaner air faster.
Auto-delivery saves time, money and keeps filters on schedule.
Allergens like dust and pollen are a concern. MERV rated air filters give advantages for your indoor air quality and HVAC efficiency.
EPA says MERV filters provide superior air filtration. Unlike basic filters that primarily catch larger dust particles and lint, Filterbuy MERV rated filters are designed to capture a much wider range of microscopic airborne contaminants. This includes common allergens, finer particles and even some smoke and smog particles that might be present in the air.
The right MERV filter protects your HVAC system. These filters stop dust from gathering in your HVAC. This reduces stress on your unit and maintains airflow.
Families who made the switch to Filterbuy MERV rated 13x21x1 air filter for allergies noticed immediate improvements.
“GREAT filters, BEST price online (for MERV-13, 21x13x1 and MERV-11, 13X21X1 at least. Trust me, I shopped and researched for a month before purchasing!) And AMAZING customer service! If you're still getting the budget blue filters, make the change! You'll be happy you did, especially if you have asthma, allergies and pets like we do! I can tell there is less dust settling in the house after only 2 weeks!” - Elizabeth B.
What about MERV ratings on air filters? MERV means Minimum Efficiency Reporting Value. It’s a system that rates how effective a filter is at catching different-sized particles. Here's a quick breakdown:
Filterbuy 13x21x1 air filter MERV 8 captures 90% of airborne particles. It’s a great all around filter that is versatile in a lot of homes.
Filterbuy 13x21x1 air filter MERV 11 captures 95% of airborne particles. It is a good choice for homes with allergy sufferers.
Filterbuy 13x21x1 air filter MERV 13 is a premium hospital grade filter that captures 98% of airborne particles.
Keeping your home's air clean and your HVAC running smoothly just got easier. With Filterbuy automatic filter delivery service, say bye to forgetting to replace your air filter.
Sign up and choose your preferred delivery schedule. Then we'll ship your new filters to your door right when you need them. You'll save 5% on every future order, giving you convenience and savings. It's an effortless way to ensure consistent indoor air quality. This checks one more task off your busy to-do list.
At Filterbuy, we specialize in American-made, MERV-rated filters that are proven to reduce airborne irritants while remaining budget-friendly.
Our 13x21x1 pleated air filters are crafted with electrostatically charged pleated media to trap microscopic particles efficiently—ideal for allergy-prone households. Plus, with fast shipping from regional warehouses, it’s easier than ever to get clean air right when you need it.
Whether you're replacing a single filter or stocking up for the season, we offer convenient subscription options and bulk pricing to help you save more over time—all with the trusted performance and quality Filterbuy is known for.
It captures dust, pollen, pet dander, and other airborne particles to improve indoor air quality and protect your HVAC system from buildup and strain.
Typically every 60 to 90 days. If you have pets, allergies, or a high-use HVAC system, consider changing it every 30 days for optimal performance.
MERV 8: Basic dust and lint protection
MERV 11: Ideal for homes with pets or allergies
MERV 13: Higher protection against fine particles and allergens Filterbuy recommends MERV 11 for balanced airflow and allergen control.
It’s a less common size, but it’s still widely used in specific HVAC systems. Filterbuy manufactures this size in various MERV ratings and ships quickly from U.S. warehouses.
Yes! With Filterbuy’s auto-delivery option, you can set your replacement schedule and never worry about missing a filter change.
Turn off your HVAC system's power.
Have your best 13x21x1 air filter ready.
Carefully remove the old air filter.
Note the direction of the airflow arrows on the old filter.
Insert the new air filter into the slot.
If there is a cover over the filter, replace it securely.
Turn the power back on.
