How frequently you should change your air filters may depend on the following:
- Air filter type
- Complete indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the house
For basic 1"–3" air filters, manufacturers typically instruct you to get new ones every 30–60 days. If you have from light to moderate allergies, you could upgrade the air filter or get new ones even more frequently.
Or, if you reside a more rural area or less occupied residence (like a vacation house) and there are not as many cars around, annually could be regular enough.
Here are averages that could help you know 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