Indiana: 812-200-0978 Cincinnati: 513-216-0862 Kentucky: 859-429-9169

How Often Should You Change Your Furnace Filter?

The HVAC system in your home has many important components. However, some homeowners forget that the air filter is one of the most crucial parts when it comes to your heating system or air conditioner working at peak performance. Without the air filter, your HVAC system wouldn’t be able to work properly and would circulate harmful airborne contaminants throughout your home.

So, how often should you change your furnace filter? There’s a general rule of thumb you can follow, but it’s important to know that several factors may affect how often you replace the filter. We’ll go over everything you need to know below.

The Importance of Changing Furnace Filters

Before we can discuss when to replace furnace filters, it’s critical to understand why this simple maintenance task is so important. As you may or may not know, many airborne pollutants can set up shop inside your home. These pollutants can include pollen, dust, pet dander, and mold spores — among various others.

Your air filter’s job is to collect and trap these harmful particles before they have a chance to circulate throughout your living spaces. If the air filter becomes clogged or dirty, this can negatively impact the indoor air quality in your home. However, this isn’t the only potential consequence. A dirty air filter will limit the airflow inside your home, which can make your furnace work harder to meet your heating needs. When your furnace has to use extra energy, this can cause your energy bills to rise.

Here are some warning signs that can suggest it’s time to replace your furnace air filter:

5 Signs to Replace Your Furnace Filter infographic

The General Rule of Thumb

So, how often should you change your furnace filter? Generally speaking, you should replace it every 90 days.

However, it’s important to mention that you might want to replace your filter more frequently depending on your specific needs.

Additional Factors to Consider

It can be challenging to know when to replace furnace filters, especially if you’ve never attempted this maintenance task on your own before. There are many factors that can affect your specific replacement schedule, including the type of furnace filter you use, the number of pets in your home, and more. Let’s discuss them in more detail below.

Filter Type

Furnace air filters can come in all shapes and sizes. As you can imagine, the type of filter you use can affect how often you should change it. For example, thicker filters (about five inches) can typically be replaced once every 12 months. However, if you have a thinner filter that’s within the one to two-inch range, you’ll want to swap out the filters every two months. Don’t overlook the importance of the filter size you’re using.


Pets bring a lot of joy and excitement to everyday life, but many of them leave behind pet dander that can worsen allergy and asthma symptoms. So, how often should you change your furnace filter if you have furry friends?

In general, you’ll most likely want to replace the filter once every 60 days. If you have more than one pet, consider upping the frequency to every 30 days.

Household Size

It can be challenging to know when to replace furnace filters, especially if you have a large household. As you probably know, constant foot traffic inside your home can lead to many pollutants entering through the front door. Of course — these pollutants won’t leave on their own. Fortunately, the furnace filter is always hard at work trapping these harmful airborne particles.

So, how often should you change your furnace filter if you have a large household? All-in-all, it’s best to change the air filter on a more frequent basis. Instead of every 90 days, consider following a 60-day schedule. Don’t forget to take the other factors listed in this guide into account as well.


Poor indoor air quality can pose a potential threat to those who have allergies and asthma. Many airborne contaminants, such as mold spores, dust, and pollen, can lead to various health problems, such as coughing, sneezing, headaches, and difficulty breathing.

If members of your family have allergies or asthma, you’ll want to avoid having a clogged filter as much as possible. In the end, it’s a good idea to replace the filter every 30 or 60 days.

Schedule Heating Maintenance With Arlinghaus

Now that you know when to replace furnace filters, it’s time to consider your heating system’s maintenance needs. Changing the air filter in your furnace is only one of the many maintenance tasks you should complete regularly. It’s important to routinely check, test, and clean your heating system to ensure it will work when you need it most.

Fortunately, this is where Arlinghaus can help. Our residential HVAC contractors offer dependable heating maintenance services in Erlanger, KY, and the surrounding areas like Loveland, Clermont, and Mason — to name just a few. When you schedule one of these services, you can feel confident that your furnace will be ready to face the cold weather. Plus, you can rest assured knowing that the air in your home will be clean and safe.

Contact us today to learn more about our Hamilton County heating and air conditioning services!

Sharing is caring!