How to Change Your Apartment Air Filter (3 Minutes, Better Air, Lower Bills)

Appliances & Tech5 min readSeptember 7, 2026

Your HVAC system circulates air through your apartment continuously, and every cubic foot passes through a filter first, capturing dust, pet hair, pollen, and other particles. When that filter clogs, the system works harder to move the same amount of air — higher energy bills, a hotter motor with a shorter lifespan, and worse air quality. Changing it every 60 to 90 days fixes all of that at once, and most renters never do it, even when their lease says it’s their job.

What you need

A replacement filter in the correct size — printed on the edge of your current filter as three numbers, like 16x20x1 (write it down or photograph it before shopping). A basic pleated filter runs $8–$15 at any hardware store, Walmart, or Amazon. Skip ultra-high-density HEPA filters in standard systems; they can restrict airflow too much.

Step 1: Find the filter

It’s usually in one of three places: inside the air handler unit (often in a closet or utility space), behind a large return air vent on the wall or ceiling, or in a slot on the furnace. The return vent is the large grille — often 10x20 inches or bigger — that pulls air in rather than blowing it out.

Step 2: Remove the old filter

Open the vent cover or access panel — most swing on hinges or unscrew at the corners. Slide the filter out and note the direction of the arrow printed on its frame; you’ll match it when installing the new one. A visibly gray, dusty, or nearly clogged filter means your system’s been working harder than it should.

Step 3: Install the new filter

Insert it with the arrow pointing the same direction as the old one — toward the air handler, away from the return duct. Getting this backward is the most common mistake; a reversed filter won’t seat properly and may let air bypass it entirely. Slide it in fully and close the panel.

Step 4: Set a reminder

Set a phone reminder for 90 days out (60 days if you have pets or allergies), and write the install date on the filter’s edge with a marker. Even better: set up a subscription with a 90-day delivery interval so the filter just shows up.

Mistakes to avoid

Installing the filter backward. Match the arrow direction exactly.
Using an overly restrictive filter. MERV 13+ filters can reduce airflow in systems not built for them — MERV 8–11 pleated filters strike the right balance for most apartment HVAC systems.

Find the filter, note the size, swap it in with the arrow pointing toward the unit, close the panel, and set a 90-day reminder. Three minutes for better air quality, a lower bill, and a longer-lasting system.