MERV 8 VS MERV 13? What’s The Difference?

Using the right air filter is detrimental to your AC’s efficiency. That’s why choosing the right MERV rating for your home is a critical step.

MERV 8 is enough for filtering light debris such as mold, pollen, dust, and pet fluff. MERV 13 filters can filter out microscopic particles to reduce asthma and allergy triggers.

You might not find any difference between a MERV 8 and a MERV 13 filter upon a glance. Both can filter specks of dust and other things that can degrade the quality of the indoor air. But in reality, these filters deal with different particles, and one might be better than the other for your particular needs. 


MERV 8 is the cheapest option for a well-rounded primary filter. It can filter out things like pollen, dust mites, and mold. On the other hand, MERV 13 filters have a high capacity that can trap smaller particles like sneeze residue. MERV 13 can filter out more particles, but it is a more expensive option. 

What Is MERV Rating?

According to the United States Environmental Protection Agency, MERV stands for “Minimum Efficiency Reporting Values.” MERV is a way to describe a filter’s capacity to filter out particles by size.

This method of measuring and reporting performance is useful to compare what different types of filters can do. MERV reporting was created by the American Society of Heating, Refrigerating, and Air Conditioning Engineers. 

The lowest MERV rating is MERV 1-4, usually seen on residential furnaces, prefilters, and window AC units. The highest MERV rating is at MERV 20, which can be found on smoking lounges, hospitals, orthopedic surgery rooms, manufacturing facilities, and more. 

Lower-level MERV filters are typically used for prefilters to enhance the effect of the final filter. However, a final filter can stand-alone, albeit with shorter working life. 

What Are The Different Categories Of MERV Ratings?

MERV ratings are based on the size of particles that a filter can trap. Filters in the MERV 1-4 category can usually trap particles down to 10-micron particles. MERV 5-8 can filter out particles up to 3-micron size and typically found on residential buildings.

Although cheaper, filters in this category can only catch light debris like spores, pollen, dust lint, carpet fibers, and dust mites. It can still be helpful for people who have a limited budget. Getting these cheaper filters is better than having nothing installed in your system. 

Filters from MERV 9-12 can filter down smaller particles for up to 1-micron. High-capacity filters are rated MERV 13 and beyond. These filters can catch 0.3-microns and are recommended if you or other family members have a medical respiratory condition. 

Is A Higher or Lower MERV Rating Better?

The short answer is: yes, a higher MERV rating means better performance in filtering. A higher rating means that your AC unit can recirculate cleaner air around your area. MERV 13 and higher-rated filters can prevent more particles than MERV 8 and below. Better MERV ratings can catch a higher particle percentage. 

Filters in the MERV 9 to 12 range are considered to have the best balance in both budget and performance. These filters are recommended for families who have pets or family members prone to allergies. These filters can sift auto-emissions and welding fumes as well. 

MERV 13 filters and above are recommended for people who have asthma or are more sensitive to allergens. These can also keep most bacteria and sneeze residues at bay. You can also use this if someone in your immediate surroundings is a heavy smoker. 

Factors That Affect Which MERV Ratings To Choose

Like most products in the market, both the MERV 8 and MERV 13 filters are helpful to different types of users. Additionally, you can use a combination of filters to get a better outcome or prolonging the life of a filter with a high MERV rating. While you’re on the market for a new filter, consider the following factors when choosing your product. 

Filter Performance

The filter performance is easily identifiable: the higher the number is, the better. Take note that while high-capacity filters have higher filtration potential, it also has a higher price tag.

Filter Cost And Replacement

You have several options when choosing your new air filter. In most cases, these options only differ on the particle size that it can trap. When choosing a filter, consider the cost and availability of the replacement. You will need filters as long as you will use your AC. Get the best option based on all financial considerations. 

Filter Needs

Do you need a filter that can catch all dust and lint, viruses, bacteria, and even the smog from the streets? Or do you want a filter that can reduce the dust particles in your area? Either way, deciding on what’s best for you and your family will heavily affect your filter spendings. 


According to EPA, a MERV 8 rated filter is any filter that can trap up to 3-micron particles with an efficiency of 84.9%. This filter type is usually made with synthetic media and a decent option for the basic filtering of allergens and dust. Filters in this category are also less likely to cause a pressure drop, affecting the airflow rates negatively. 

MERV 8 is the minimum basis on which most commercial workplaces or buildings apply to their infrastructures. It can catch almost 90% of all airborne particles. Users need to replace this every 60-90 days, depending on how often they use their AC. 


On the other hand, a MERV 13 filter can sift all the particles that a MERV 8 filter can do. In addition to these basic particles, a MERV 13 filter can take up to 0.30 particle size. With this filter size, things like tobacco and sneezes are filtered. 

Like other filters in the market, the MERV 13 must be replaced every 60-90 days. Otherwise, the bacteria, pollen, mold, dust, dust mites, and other dirty stuff will turn into a dirt and grime layer, which can cause clogs and freezing of the condenser coil. 

MERV 8 VS MERV 13 – Which One Should You Choose?

Choose MERV 8 For Affordability

If you only need some basic filtration system, the MERV 8 can give you the best option for financial considerations. The following are the particles it can filter:

  • Dust and dust mites
  • Lint
  • Pollen 
  • Pet Dander

Choose MERV 13 For Ultimate Filtration

MERV 13 is a good option if you want to minimize potentially harmful microscopic particles like bacteria and viruses. 

All particles that MERV 8 can catch

  • Mold
  • Smog
  • Smoke
  • Bacteria
  • Virus
  • Cough or sneeze particles


MERV 8 is enough for people with basic filtration needs. Users don’t have to spend more if a MERV 8 filter can do the job perfectly. However, if the additional filtration that MERV 13 filters give is necessary, it might be worth the additional cost. Just take note that these high-capacity filters can get dirty a bit faster due to more filtration capability. 

If your AC supports prefilters, you can use both for a better and more efficient system. MERV 8 can act as a prefilter, while the MERV 13 would be the final filter.