It begins with a perplexing feeling: how do I choose the best 16x25x4 filter for my HVAC system?
Even though 16x25x4 filters may all appear to be the same (after all, they are all 4-inches thick) — appearances can be deceiving.
The best 16x25x4 filters maximize the number of particulates they capture but also maximize the clean airflow going through the HVAC system.
Top furnace air filters will also have a strong frame, quality filter material, and the correct MERV rating. In this HomeInspectorSecrets.com guide, you will learn:
- Our overall top pick for the best 16x25x4 HVAC filter
- Tips on choosing the correct 16x25x4 air filters for furnaces
- Why you should verify that the MERV rating is compatible (and won't harm your system)
- Factoring the filter undercut before you buy (all manufacturers undercut their filters)
Check out my shortlist of the best filters below, but keep reading to learn more about choosing a top 16x25x4 furnace filter and our full reviews.
| Image | Product | |||
|---|---|---|---|---|
Top Pick  | Top Pick | 1. Filtrete Allergen Defense
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| View on Amazon |
 | 2. Nordic Pure
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| View on Amazon | |
Best Budget  | Best Budget | 3. Aerostar
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| View on Amazon |
High MERV  | High MERV | 4. Filtrete Allergen Bacteria & Virus
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| View on Amazon |
Our Overall #1 Rated Pick
- 16x25x4 furnace filter (lasts for 12-months before changing)
- Uses patented 3-in-1 technology for more airflow yet more filtration
- Renowned manufacturer 3M
- Comes in a 2-pack or 4-pack
Our overall top pick for 16x25x4 furnace filters goes to 3M's Filtrete Allergen Defense. 3M is a renowned filter manufacturer and makes some of the best products in the world. These filters use 3M's patented 3-in-1 technology that increases the filtration but allows more airflow simultaneously. This 16x25x4 air filter brand comes in a 2-pack or 4-pack.
Top 4 Best 16x25x4 Furnace Filters
Don't have much time? Check out our top 4 best 16x24x4 furnace filters! Keep reading to understand the details of our picks and frequently asked questions.
What Are 16x25x4 HVAC Air Filters?
16x25x4 inch furnace filters are specially designed for HVAC systems that can hold 4-inch thick furnace air filters and 16-inches by 25-inches for the length and width.
These super-thick air filters for furnaces are also known as media filters in the HVAC industry and are some of the highest quality HVAC filters on the market. Typically, these 4-inch thick air filters brands have a MERV rating from 8 and up to 13.
Even though 16x25x4 furnace filters tend to be more expensive (such as $20 to $40 per filter) — they last significantly longer and just work better.
Read Also >> How To Clean Washable Furnace And A/C Air Filters
How Do 16x25x4 Home Furnace Filters Work?
16x25x4 inch HVAC filters work similarly to regular air filters except that they have 3+ times more surface area and larger pleats.
This means that the 16x25x4 filter will last significantly longer than a standard air filter for the home HVAC such as a 1-inch thick filter.
Since there is so much more filter material, it can capture much more particles than 1-inch filters will, but still allow strong airflow.
Most 16x25x4 furnace air filters only need to be replaced every 3-6 months, but some filters such as the 3M Filtrete furnace filters can last up to 12-months.
What Are The Different Types of 16x25x4 HVAC Air Filters?
There are a few key differences you will find among the different 16x25x4 furnace filter brands.
One of the biggest variations will be the filter strength. Some filter manufacturers add a wire mesh for strength and rigidity, and most companies have at least a paper grid pattern on the front. Once installed inside the furnace, these grid and mesh patterns help prevent the filter from buckling or folding.
You also find 16x25x4 filters that have a different filter materials with various percentages of polyester, cotton, and other synthetic or natural fibers. There are even furnace filters that are coated with activated carbon that helps capture smelly odors from cooking or pets.
How To Pick The Best 16x25x4 Air Filter For The Furnace?
Choosing the best 16x25x4 involves a few factors such as the MERV rating, frame strength, filter materials, company reputation, and pricing. Here are a few buying tips:
1. Frame Strength
The quality of the frame is always a big factor when choosing an air filter brand.
Even though 4-inch media filters usually have stronger frames than standard 1-inch filters, it is still a good thing to factor in when buying.
16x25x4 furnace filters will have a variety of filter frame strength and a grid over the front. The front grid usually has a diamond-shaped pattern or has a type of metal mesh.
Air filters for furnaces with a metal screen or mesh over the front and back are always stronger than just diamond-shaped grids. There are also 16x25x4 filters even have rubber gaskets or outer frames for additional strength and to prevent air leakage.
Read Also >> Can You Run Your HVAC System Without A Filter For A Short Period?
2. The Undercut
16x25x4 filter manufacturers all will undercut the HVAC filter dimensions anywhere from 1/16-inch and as high as 1/2-inch.
If you want to make sure that your filter is properly snug, you may want to consider the undercut dimensions provided by the manufacturer since they all tend to somewhat vary.
Another option is to install some type of gasket on the perimeter of the filter slot. You can read more details on how to properly change your air filter here.
3. MERV Rating
The MERV rating is a measurement of how well the HVAC filter captures particles in the 0.3 to 10-micron range—MERV is an acronym that stands for Minimum Efficiency Reporting Value as mentioned by the EPA.
I invite you to also read my complete guide on MERV Vs. MPR filter ratings here.
Probably the average MERV rating for media filters are in the MERV 8-11 range, but the MERV can go as high as MERV 13.
Also, most air filter brands (4 to 5 inches thick) tend to have a higher MERV rating than your average 1-2 inch thick filter. Since there is so much more surface area, it is more common to have a higher MERV rating with media filters because it is less hazardous to your HVAC system. Since it is so thick, it is less likely to get fully clogged and therefor damage your furnace.
Even though 4-inch thick filters are more resilient, you still should verify with your HVAC literature that your system can handle that particular MERV rating.
If your HVAC system can't handle the high MERV rating, at minimum it will make the system work harder but may damage your blower motor, or even burn out the entire HVAC system.
Our Reviews of the Best 16x25x4 Furnace Filters
Pick #1: Filtrete Allergen Defense
Our overall top pick for 16x25x4 filters goes to Filtrete Allergen Defense.
Made by renowned 3M, Filtrete furnace filters are very high-quality and includes a patented technology called 3-in-1.
This patented furnace air filter tech is designed to capture more microscopic particles than it's competitors but at the same time allows the clean air to pass through unobstructed.
These 16x25x4 pleated furnace filters for allergies need to only be changed once every 12-months.
These Filtrete furnace filters are rated at MERV 11 and work so good that they can turn your HVAC system into a whole house air purifier. Use these thick pleated 4-inch filters to capture large allergens like pet dander, mold spores but also micro-particles like smoke and smog.
Pros
Cons
Pick #2: Nordic Pure
Nordic Pure is one of the leading filter manufacturers in North America, and they were the first company to introduce a pleated carbon filter to America.
This 2-pack of 16x25x4 inch filters do a great job of filtering allergens, dust, pollen, and other particulates from your home—turning the HVAC system into an air purifier.
Rated at MERV 12, these 4-inch pleated filters are recommended to be changed every 6-months. These 16x25-4 inch filters are proudly made in the USA, and Nordic Pure is based in Texas.
They are electrostatic, anti-microbial, and made with heavy duty beverage board frames. Nordic Pure also makes a line of eco-friendly and recycled air filters for furnaces.
Pros
Cons
Pick #3: Aerostar
Aerostar makes a fantastic budget-friendly 6-pack of 16x25x4 inch filters for your home HVAC system.
These furnace filters are pleated and includes a diamond-shaped cardboard grid on the top for rigidity and strength.
This 6-pack filter package is rated at MERV 11 and designed to capture pollen, mold spores, dust, dander, smoke, smog, and other fine particulates.
Aerostar recommends changing these filters every 3-6 months, and at their price point, it is a good deal.
These air filters for the home HVAC are manufactured in the USA by Filtration Group and are made with synthetic and electrostatic filter material.
Pros
Cons
Pick #4: Filtrete Allergen Bacteria & Virus
Allergen Bacteria & Virus is another excellent line of Filtrete furnace filters for allergies that we recommend for homeowners.
If you want the next level of filtration capacity, these MERV 12 rated filters are for you.
They are designed to capture 54% more microscopic particles such as pet dander, pollen, viruses, bacteria, and smoke.
When you buy high MERV filters though, please make sure that your HVAC system can handle it (consult the manufacturer manual).
3M is renowned furnace air filter manufacturer, and they use their patented 3-in-1 technology with their Filtrete furnace filters. 3-in-1 technology allows more airflow through the system and at the same time captures more particulates that competing filters.
Pros
Cons
Our Top Pick: Filtrete Allergen Defense
We chose the 3M Allergen Defense 16x25x4 filter as our top pick for these reasons:
1. Quality Company
3M is renowned as a global manufacturer and their furnace filters are at the top of the pack. With other filter companies, you aren't always sure what you are getting even with their advertised MERV ratings. You may be spending a little more with Filtrete filters, but you can be assured of the quality.
2. 3-in-1 Technology
The patented 3-in-1 technology by 3M is an air filter design that increases the filtration capacity but at the same time allows more airflow through the filter. And that's what you want filters to do—allow as much airflow as possible while filtering out bad particles. This filter is rated at MERV 11.
3. Infrequent Filter Changes
Since this is a 4-inch pleated furnace filter, 3M recommends only changing the filter every 12-months. And admittedly, 12-months may be a bit unrealistic, and you may need to change it more often than that. But still, these Filtrete 4-inch pleated filters last significantly longer than the competition.
