Customer reviews from Filterbuy
Filterbuy - 21x21x4 MERV 13 Smoke & Allergy Defense, Electrostatic Pleated HVAC AC Furnace Air Filters Replacement (4-Pack) - Blue
Average customer rating
4.1
(1,155 Reviews)
Rating breakdown 1,155 reviews
5 Stars
716
4 Stars
109
3 Stars
127
2 Stars
88
1 Star
115
Customer Reviews for Filterbuy - 21x21x4 MERV 13 Smoke & Allergy Defense, Electrostatic Pleated HVAC AC Furnace Air Filters Replacement (4-Pack) - Blue
Customer Rating
5
Fast service on a good quality product
on September 3, 2026
Posted by: Customer
We’ve been using the MERV 13 filters for a couple of years now, and have been very pleased with the results. Worth the slight additional cost.
Written by a customer while visiting Filterbuy
Customer Rating
5
love the price and quality
on August 28, 2026
Posted by: Customer
love the price and quality of the filters have been buying from you for 7 years now. We could have never done the fires here in Idaho without the filters from you guys.
Written by a customer while visiting Filterbuy
Customer Rating
1
Very misleading sizes
on August 28, 2026
Posted by: Customer
Filterbuy products are not what they claim. Just went to replace my filter with a new one from Filterbuy brand filters and it’s a half inch smaller in every dimension. Filter doesn’t fit the slot well and wobbles around.
Written by a customer while visiting Filterbuy
Customer Rating
5
Auto Pilot Filter Replacement
on August 26, 2026
Posted by: Customer
We the autoship feature, it makes it easy to remember to replace the filters in a timely fashion. Pay attention to the actual dimensions provided in the product descriptions, they run a bit smaller!
Written by a customer while visiting Filterbuy
Customer Rating
5
Super filter
on August 23, 2026
Posted by: Customer
This is a great filter for controlling dust in the house and the price is responsible
Written by a customer while visiting Filterbuy
Customer Rating
5
Well made filters
on August 23, 2026
Posted by: Customer
The construction and materials used in these filters seem to be top-notch. At the same time they're very competitively priced. I'm a regular customer.
Written by a customer while visiting Filterbuy
Customer Rating
5
Great Buy on Great Filters
on August 13, 2026
Posted by: Customer
Have been using these filters for years and they always do very well keeping the air clean.
Written by a customer while visiting Filterbuy
Customer Rating
5
Very effective
on August 5, 2026
Posted by: Customer
With the recent particle and smoke from wildfires, these filters kept our indoor air clean.
Written by a customer while visiting Filterbuy