How often you should change your air filters might depend on the following:
- Air filter kind
- Overall indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers often tell you to replace them every 30–60 days. If you have from light to moderate allergies, you could install a better air filter or replace them even more often.
Or, if you're in a more rural area or less occupied house (like a vacation home) and there are fewer cars around, every year may be often enough.
Here are averages that can help you decide how regularly you should get a new air filter at home:
- Vacation house or one occupant and no pets or allergies: every 6–12 months
- Ordinary suburban home without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days