How Often to Change Air Filter in Homes? Here Are the Updated Guidelines

Owning your home comes with a lot of tedious tasks that must be done in order to maintain your property.

Some of them you probably anticipate doing on an annual basis, such as having your heating and cooling system serviced. Others are a little less clear. For example, how often should you really be changing your home air filter?

Home Air Filter Being Changed

The Short Answer: In a home occupied nearly all year round, most professionals recommend changing your home air filter every 60-90 days depending on a number of factors described in detail below, including pets, allergies, etc.

The Long Answer: Knowing when to change your home air filter can be a little bit tricky for a number of reasons. Every home is slightly different in its makeup which can alter the answer to this commonly asked question. Even the air filter you purchase can play a role in how often you need to replace this essential piece of equipment. While the answer may vary from home to home, it’s crucial that you learn exactly what your home needs in order to function properly.

A good rule of thumb is to change your air filter every ninety days. That means that you should be replacing your air filter with a fresh and clean version at least once a quarter. However, that rule of thumb may not be the safest option if you have pets, allergies, or even a vacation home.

How Do Pets Affect Your Air Filter?

Pets can certainly complicate the matter of how often you need to change your home air filter. Adding a cat or dog into the mix produces more pet dander, dust, and fur that floats through the air of your home. All of these items come together to clog up the air flow in your filter. This is why experts recommend replacing your filter much sooner if you have a pet in the house. When Fido is a bonafide member of the family, you should consider replacing your air filter at least every sixty days.

What about those animal lovers who have multiple pets? The onslaught of dander, dust, and fur can certainly keep your HVAC system from running smoothly. Homeowners with more than one cat or dog should really be replacing their air filter every thirty days like clockwork.

Allergies Make a Difference

Changing your home air filter more regularly is just as important if you suffer from allergies. The excess dust, dander, and other air contaminants become trapped in your air filter and find their way into your home. This can make for runny noses, terrible coughs, and other allergy symptoms that you would rather do without. Some people with severe allergies prefer to replace their air filter every two weeks, just to find some relief from their symptoms. Others with milder allergies can often get away with replacing their air filter just once every thirty days.

Low Occupancy Extends Lifespans

What if you don’t actually reside in the home full-time? Vacation homes that are only occupied for a small portion of the year are a separate consideration that should be made. Because no one is living in the home, there are fewer air contaminants getting trapped in your air filter. You can prolong the amount of time between air filter changes significantly. Many of these types of homeowners only change their filters every six months to one year.

Even single individuals who live alone might be able to extend the lifespan of their air filter. If you live alone and have no pets in the picture, you can try changing your air filter just once every four to six months.

Why Changing Your Air Filter Matters

Sure, you know that your heating and cooling system plays a huge role in the overall comfort of your home. Nobody wants to endure the sweltering summer heat without the modern convenience of air conditioning. But does it really matter whether or not you change your air filter on a regular basis?

If you aren’t totally convinced that changing your air filter is the right move for your home, check out a few of these top reasons to replace it regularly.

Save Money on Repair Costs

The truth is that changing your air filter is essential to helping your HVAC system run smoothly. Over time, your air filter collects the dust, dirt, pet dander, and other air contaminants that float around your home. While the air filter may be pristine and white when you place it in the return, it often turns grey and dusty as the months pass by. This deterioration causes significant strain on your HVAC system.

A dirty air conditioner can lead to some serious strain on your system. Over time, that extra work results in much-needed repairs or you could face a shortened lifespan of your unit. By replacing your air filter, you are helping to keep the parts of your air conditioner cleaner and thereby reducing some of its wear and tear. You could potentially save yourself thousands of dollars by performing this one simple task.

Save Money on Your Cooling Bill

Have you ever wondered what you could do to reduce your electricity bill at the end of the month? Especially during the summertime, those bills can creep to astronomical proportions. You can do yourself a favor and reduce some of those costs by investing in a new air filter for your HVAC system.

When the air filter is dirty and clogged, your HVAC unit has to work much harder to push the fresh air through and into your home. This extra work uses up more electricity and can really put a dent in your pocketbook over time. Imagine how much money you could save by investing in a relatively inexpensive air filter every few months!

Improve Your Indoor Air Quality

Maybe you get frequent headaches when you spend too much time indoors. Perhaps you are one of those unfortunate individuals who suffers from extreme allergies when exposed to poor indoor air quality. According to the Environmental Protection Agency (EPA), the air inside our homes is two to five times more polluted than the outdoor air. This can lead to all sorts of symptoms that you never realized were connected to the overall functioning of your HVAC system.

A clean air filter for your home means that you can stop breathing in dust mites, pet dander, and other tiny particles. Instead, you can take a big gulp of fresh air and know that you are doing something great for your health.

Rating an Air Filter: The MERV Scale

One of the most difficult parts of changing your air filter is understanding what kind of replacement filter you should purchase. Many of the leading companies will refer to one specific scale to let you know how efficient their air filters truly are. Experts refer to this scale as the MERV scale, short for Minimum Efficiency Reporting Value.

This specific scale gives professionals a standard to refer to when rating the quality of their air filters. The entire process starts with a clean air filter that is then exposed to different particle sizes. Each particle size is forced through the air filter six times with a special type of sprayer. They test twelve different particle sizes to determine which filters are the most efficient at removing different contaminants from the air.

The MERV scale for air filters has sixteen different categories that your air filter can fall into.

MERV 1 – 4

The lowest ratings on the scale remove the least number of contaminants from the air around you. They may remove common particles such as pollen, dust mites, and carpet fibers from your home. Their efficiency is extremely low, but so is their price point. These are great for budget-conscious consumers who do not suffer from allergies or have major concerns about the quality of their indoor air.

MERV 5 – 8

These filters are a little more effective than those in the most basic category. They are capable of handling mold spores, finer dusts like that caused by cement, and even hair spray particles. Filters that have this rating are definitely a step up, and their price is likely to reflect that jump in quality. Keep in mind that they are still inefficient at trapping particles that are going to be smaller than one micron.

Most experts recommend looking for an MERV score ranging from six to eight to give you the most value for your dollar. Not only are these air filters affordable, they also allow your HVAC system to function smoothly without any additional strain. This keeps your HVAC bill as low as possible while still maintaining excellent indoor air quality.

MERV 9 – 12

An air filter with a rating of nine through twelve is considered to be very high efficiency. It can remove extremely small particles from the air, including auto emissions. At this rating, your HVAC system will be forced to work a little harder to push the cooled air into your home. The weave of the air filter makes it much more difficult for the HVAC system to function easily and without strain. These filters are great for homeowners with allergies, but they may not be as great for your overall electricity bill.

MERV 13 – 16

A filter with this rating is considered to be maximum efficiency. These are not generally recommended for use in a home heating and cooling system. They are much better suited to commercial buildings where indoor air quality is of the utmost concern. MERV ratings ranging from thirteen to sixteen are capable of filtering out particles as small as 0.3 microns – quite an accomplishment! This includes bacteria, tobacco smoke, and more.

Shopping Considerations

Beyond the MERV score of your air filter, what else should you really be looking for in a potential filter? Here are just a few of the things that you may want to consider:


Every home has a different return size, so make sure you are paying attention when you head out to the store! Check the size of your current air filter to ensure that you are purchasing the perfect fit.


Many homeowners are tempted to purchase those blue air filters that come in a cardboard frame. They are made of one single sheet of fiberglass that removes only the largest particles from the air. These are a very basic means of protecting your HVAC system, but it may not hold up to prevent repairs for the long run. Consider that fact that many builders use these in new construction homes to help keep their costs low.

Instead, you should be looking for a pleated air filter. The more pleats an air filter has, the more likely it will be to remove air pollutants from your indoor air. If you can’t find the MERV rating on the packaging, looking for an air filter with lots of pleats per foot is a great way to determine the overall efficiency of filter.


Do you hate the idea of throwing away your air filter every couple of months? You can save more money in the long run by investing in a washable air filter right now. While this does create an extra chore for you every so often, it can be a great way to be environmentally friendly. It also allows you to change your air filter more regularly without any additional cost to you. You can definitely improve the quality of your indoor air when you are thoroughly washing your air filter on a regular basis.

The Bottom Line

When it comes to changing your air filter, you should know exactly what to expect. Every home is different when it comes to how often your air filter needs to be replaced. Consider your lifestyle and how many people (or pets!) live in your home. All of these factors come together to determine how often you should really be changing your air filter.

You can live a healthier life and extend the lifespan of your HVAC unit when you adhere to the proper guidelines about how often to change your air filter. Head to the store prepared with some of these facts to help you make the wisest investment possible for your next air filter purchase!