How Often Should You Change Air Filters?

• Published: 10/09/25
• Updated: 10/09/25

When was the last time you checked your air filter? If you can’t remember, you’re not alone — and it might be costing you more than you think. Knowing when to change air filters in your home is one of the simplest and most effective ways to keep your HVAC system running efficiently and your indoor air quality high.

In this guide, we’ll break down how often to change air filters, what factors influence timing, and why staying on top of this small task can save you big in the long run.

Why Changing Air Filters Matters

Air filters trap dust, allergens, pet dander, and other particles from circulating through your HVAC system and into your living space. Over time, these filters clog up, forcing your system to work harder. This ends up leading to higher energy bills, unnecessary wear and tear, and poor air quality.

Ignoring air filter changes can even lead to bigger problems like:

• Increased allergy symptoms or respiratory issues
• System overheating or breakdown
• A musty or “weird” smell coming from the vents
• A dusty home even after regular cleaning

How Often Should You Really Change Air Filters?

The general rule of thumb: every 1 to 3 months.

But this depends on your household and environment. Here’s a breakdown:

• Single occupant, no pets – Change every 3 months
• Family home with one or more pets – Change every 1 to 2 months
• Households with allergy or asthma sufferers – Change every 1 to 1.5 months
• Homes in high pollen or dusty environments – Change monthly
• Vacation or part-time homes – Change every 6 months

If you live in the Southeast humidity, pollen, and dust are common issues across the region. As such, it’s a good idea to check your filters every month and replace them if they look dirty.

Factors That Affect Filter Replacement Frequency

Still wondering when to change air filters? These variables can shorten the filter’s life:

• Pets: Pet hair and dander clog filters quickly.
• Smoking indoors: Contributes to filter buildup.
• Outdoor air quality: High pollen or dust levels = more frequent changes.
• Home renovations: Drywall dust, paint particles, etc., clog filters fast.
• Type of filter: HEPA and pleated filters may last longer but can still clog sooner under heavy use.

Air Filter Guidelines for Commercial Properties

If you manage an office, retail space, or facility, your air filtration needs are more complex than those of a typical home — and the stakes are often higher. Dirty filters in commercial HVAC systems can lead to costly downtime, poor indoor air quality for employees and customers, and reduced system efficiency.

Here’s what business owners and facility managers should know:

• Check filters monthly and change them at least every 1–2 months, depending on usage, industry, and occupancy.
• High-traffic businesses like gyms, restaurants, and medical offices may need to change filters every 3–4 weeks due to increased dust, dander, and airborne contaminants.
• Consider using commercial-grade pleated filters or HEPA filters for enhanced filtration.
• Schedule quarterly HVAC inspections to ensure air quality and efficiency across all zones.
• Implement a filter log system or partner with a trusted HVAC provider (like Wilson’s) to stay ahead of replacement schedules and avoid emergency repairs.

Need help creating a filter maintenance plan for your commercial property? Wilson’s offers HVAC maintenance programs designed to meet the needs of small businesses, medical offices, religious centers, and multi-unit facilities.

Signs It’s Time to Change Your Air Filter

Not sure whether your filter needs replacing? Watch for these signs:

• Dust buildup on surfaces despite cleaning
• HVAC system running longer or less effectively
• Increased allergy or asthma symptoms
• A musty, stale, or “weird” smell from your AC
• Visible dirt or discoloration on the filter itself

If your AC smells musty or your home is unusually dusty, it’s time to change the air filter — and fast.

What Happens If You Don’t Change Air Filters Regularly?

It’s easy to forget about your air filter… until it’s too late! Skipping filter changes doesn’t just affect comfort; it can put real strain on your HVAC system and your wallet.

Failing to change air filters can lead to more than just discomfort. Long-term neglect may result in:

• Frozen evaporator coils
• Costly system repairs
• Shortened HVAC system lifespan
• A spike in utility bills
• Dangerous air quality for young children, seniors, or those with respiratory issues

A dirty filter is a silent system killer. Don’t wait for the damage to add up! Protect your home, health, and HVAC system with one simple step.

Schedule Your AC Maintenance with Wilson’s 

Changing your air filter is one of the simplest things you can do to protect your HVAC system and your family’s health. At Wilson’s, we recommend checking your filters monthly (especially during heavy-use seasons) and replacing them as needed. Need help or not sure what type of filter you need? Our team is just a call away. We’ll make sure your system is running clean and efficiently. Contact us today to schedule your service or learn about our Maintenance Plans.