Common Furnace Filter Sizes and Where to Buy Them

There are different types of furnaces, but most use a common furnace filter size. So, before replacing your filter, you need to know which size and type you need.  

Your brand of furnace may need an electrostatic or media filter of a specific size.  Look at the old furnace filter to see which size and type it uses.  

Don’t overlook the importance of furnace filter replacement. Changing your filter regularly will improve your HVAC system’s efficiency, so it cools, heats, or cleans your air using less energy. That saves you money in the long run. Plus, a clean filter keeps your air quality high.   

Let’s look at the most common furnace filter sizes and where to buy furnace filters. 

Common Furnace Filter Sizes: 

There is not one standard furnace filter size that will fit all models, but the most common filter dimensions are: 

• 10x20 
• 14x20
• 16x24 

• 18x30 
• 12x12 
• 14x24 

• 16x25 
• 20x20 
• 12x20 
• 14x25 
• 18x18 

• 20x24 
• 12x24 
• 14x30 
• 18x20 
• 20x25 

• 12x30 
• 15x20 
• 18x24 
• 20x30 
• 12x36 

• 16x20 
• 18x25 
• 24x24 
• 25x25 

You can use your existing filter as a reference guide for sizing. The filter dimensions should be printed on its frame as length x width x height. 

Media Filters and Where to Buy Them 

Media filters are the workhorses of the filter world, cleaning out more particles from your air.  

Media filters are made of deeply pleated, paper-like material. They’re seven times better than a standard filter at removing dust and other particles and have a longer lifespan than other filters (up to two years longer). 

Media filters are commonly used in HVAC appliances, but are sometimes hard to find at stores. At Appleby Systems, we carry media 5-inch furnace filters, with the following specifications:  

M1 1056 air filter – Dimensions/Sizes: M1 15 3/8 x 25 1/2 x 5 1/4 (16 x 25 x 5 furnace filter)
M0 1056 air filter – Dimensions/sizes: M0 15 3/8 x 21 7/8 x 5 1/4 (16 x 22 x 5 furnace filter)
M8 1056 air filter – Dimensions/Sizes: M8 20 1/4 x 25 3/8 x 5 1/4 (20 x 25 x 5 furnace filter) 

These filters all have a great efficiency rating to help you save on energy usage. Their MERV (or minimum efficiency rating value) is 11. The higher the MERV rating, the smaller the particle size the filter can collect.  

While you’re out grabbing filters, we suggest you purchase them in packs. Not only does this stop you from making frequent shopping trips, it allows you to switch your filters more frequently.  

Remember, it’s ideal to change the filter in most HVAC appliances once a month.  

Not sure where to buy your furnace filters? Contact us at Appleby Systems. We know the most common furnace filter sizes and can show you which is right for your appliance.  

^References: 

^{https://www.hvac.com/faq/common-air-filter-sizes-air-filters-size/} 

^{https://tempcontrolnj.com/media-filters-vs-standard-furnace-filters/}