How Often Should You Change Your Furnace Filters?

How often you should change your furnace filter depends on what type of filter you have. It’s also based on your household’s needs, with most households changing their filters monthly or annually. In the following article, we outline things to consider when determining how often to replace a furnace filter, including:

Continue reading below for more details on how often to change a furnace filter.

Regularly changing your furnace filter is a simple way to keep your furnace’s internal components clean. Expect to switch it out at least every 3 months with a standard furnace filter. If you have someone in your home who has allergies or asthma, or if your household contains pets, changing the filter monthly promotes better air quality.

High-efficiency filters provide a more hands-off option. Depending on your household's usage, you can expect to replace these filters every 6-12 months. If you’re not sure, refer to the manufacturer’s recommendations for your furnace, which has tailored information on how often to change the filter.

The frequency at which you should replace your furnace filter depends on a range of factors specific to your household. For example, fiberglass, pleated, and HEPA filters should be changed at varying frequencies. Also, how often your system runs affects how quickly the filter accumulates particles.

The size of your home and the number of household members affect how often you should change your filter. Similarly, if you have pets that shed dander or hair, you may benefit from more frequent filter replacement. Local air quality and pollution levels also affect the lifespan of your furnace filter.

If you’re already changing your furnace filter at regular intervals but wonder if it's enough, there are some signs to watch for that indicate it’s not doing its job. For example, if you notice dust buildup around your vents or reduced airflow from the registers, your filter may be clogged. If you notice an uptick in allergy or asthma symptoms, this can also indicate you need to increase the frequency.

Inspecting the filter for visible dust and discoloration is the simplest way to determine whether it needs to be replaced. Additionally, because a dirty filter puts added strain on your furnace, you may notice that it’s running longer than usual. This indicates your filter isn’t changed frequently enough.

Maintaining a clean furnace filter seems like a simple task, but it has a significant impact on your HVAC system’s efficiency and your home’s comfort. Neglecting this routine maintenance step can force your HVAC system to work harder, contributing to higher energy bills.

Because a dirty filter increases the strain on the furnace’s motor and components, not changing the filter frequently enough can shorten the life of your system. It can cause the system to overheat or fail and take a toll on your indoor air quality.