It’s one of the most common questions we get: How often do I need to change my furnace filter? The honest answer is: it depends — but most homeowners change theirs far less often than they should. Here’s a simple guide.
Why the Filter Matters
Your furnace filter does two things: it protects your HVAC equipment from dust buildup, and it improves the air quality in your home. A clogged filter restricts airflow, forcing your furnace to work harder — which raises your energy bills, shortens the life of your system, and can cause it to overheat and shut down.
General Guidelines by Filter Type
1-inch basic fiberglass filters: Replace every 1–2 months.
1-inch pleated filters: Replace every 60–90 days.
4-inch high-efficiency filters: Replace every 6–12 months.
HEPA filters: Replace every 12 months or per manufacturer recommendation.
Change More Often If You Have…
Pets shed hair and dander that clogs filters fast — consider changing every 30–45 days if you have dogs or cats. Allergies or asthma sufferers benefit from more frequent changes too. Construction nearby or a dusty job site can clog a filter within weeks. Multiple occupants in the home also increases the load on the filter.
The Simple Check
Not sure if it’s time? Pull the filter out and hold it up to the light. If you can’t see light through it, it needs to be replaced. A dirty gray filter is a clogged filter.
Set a Reminder and Stick to It
The easiest approach: set a monthly phone reminder to check your filter. Buy a 3-pack next time you’re at the hardware store so you’re never caught without one.
Need help with furnace maintenance or have questions about the right filter for your system? All About Comfort Heating & Cooling serves Blue Springs, Grain Valley, and the KC metro. Call us at (816) 847-5557 anytime — our answering service is available 24/7.