How regularly you should install new air filters might depend on the following:
- Air filter model
- Complete indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers usually tell you to install new ones every 30–60 days. If you have from light to moderate allergies, you could get a better air filter or change them even more regularly.
Or, if you reside a more country location or less occupied home (like a vacation home) and there are fewer cars around, annually may be regular enough.
Here are averages that may help you figure out how frequently you should change the air filter at home:
- Vacation residence or lone occupant and no pets or allergies: every 6–12 months
- Average 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