How often 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 residence
For basic 1"–3" air filters, manufacturers often tell you to replace them every 30–60 days. If you deal with from light to moderate allergies, you could upgrade the air filter or replace them even more regularly.
Or, if you live a more country spot or less occupied house (like a vacation home) and there are a reduced number of cars around, each year could be frequent enough.
Here are averages that could help you decide how often you should replace the air filter at home:
- Vacation home or single occupant and no pets or allergies: every 6–12 months
- Common 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