The answer to 'how long does air filter last' is that the lifespan of an air filter can vary significantly depending on several factors. As a general guideline, most residential HVAC air filters should be replaced every 1-3 months, or as recommended by the manufacturer. However, filters may need to be changed more or less frequently depending on factors like the size of your home, the number of occupants, pet ownership, and the filter type.
Higher-quality pleated filters typically last longer than basic fiberglass filters, sometimes up to 6 months. Filters used in homes with more dust, pollen, or other airborne contaminants may need to be changed more often, even as frequently as monthly. It's important to check your filter regularly and replace it when it appears dirty or clogged to ensure your HVAC system is operating efficiently and providing clean, healthy air.