How frequently you should change your air filters may depend on the following:
- Air filter kind
- 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 have from light to moderate allergies, you could upgrade the air filter or get new ones even more often.
Or, if you're in a more country spot or less occupied home (like a vacation house) and there are a reduced number of cars around, yearly could be regular enough.
Here are averages that could help you decide how frequently you should change the air filter at home:
- Vacation home 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