How frequently you should change your air filters can depend on the following:
- Air filter model
- Overall indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the house
For basic 1"–3" air filters, manufacturers often direct you to get new ones every 30–60 days. If you suffer from light to moderate allergies, you could install a better air filter or change them even more frequently.
Or, if you reside a more rural location or less occupied house (like a vacation home) and there are not as many cars around, each year might be often enough.
Here are averages that could help you figure out how frequently you should get a new air filter at your residence:
- Vacation residence or single occupant and no pets or allergies: every 6–12 months
- Common suburban residence without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days