Buy AC and furnace replacement filters in standard or custom sizes. Order in bulk and save up to 75% off!
Fast, free shipping
Durable & long-lasting
All sizes available
Guaranteed to fit
Looking for the perfect air filter replacement?
We make finding the right HVAC filter simple. Browse our standard air conditioner filters by selecting your dimensions, or get a precision-cut custom size to match your exact specifications. Order a Custom Air Filter.
Filter King designs high-quality air filters engineered for precise fit, efficient installation, and extended service life. Ideal for professionals who demand consistent performance.
MERV ratings measure how much your filter captures – from everyday dust to fine allergens and pet dander. Find the right level for your home below.
Standard
Advanced
Ultimate
Odor Eliminator
For most homes with a 1-inch filter, 60–90 days is a reliable baseline. But filter type, thickness, pets, allergies, and local climate can all shift that window – sometimes significantly. Read this guide to find the right schedule for your home.
Read the Guide
Most US addresses receive their order within 2 business days. Check the map below to see estimated delivery times in your area.
Four fulfillment centers across the US mean your filter ships from close to home – faster to your door, built to the same standard every time.
Not happy with your stocked filter? Send it back within 30 days for a full refund – no questions asked.
We stock thousands of standard and non-standard sizes, and make custom filters to order – so you'll always find the exact fit for your system.
4.6 stars, 5243 reviews
4.5 stars, 4314 reviews
"I am a new customer and so happy I found Filter King. Their customer service is truly outstanding."
Verified Buyer
"Shipping was perfect!"
Verified Buyer
"Excellent Customer Service Support."
Verified Buyer
"Awesome experience - quick delivery and most important: PERFECT FIT !"
Verified Buyer
"Quick shipping, great price and quality"
Verified Buyer
"I called to report that my filter size was not as expected. I took a picture of the filter showing the label dimensions and a tape measure showing the actual size. They sent out replacement filter of the right size which I received the next day, no charge. Thank you!"
Verified Buyer
"Fast delivery, excellent condition. Couldn’t be happier."
Verified Buyer
"Easy"
Verified Buyer
"Always a pleasure to work with you"
Verified Buyer
"First set was off, second set was sent without even asking!!!"
Verified Buyer
Never run out of a clean filter – and cancel anytime if your plans change
Pay full price on every order
Need to remember to reorder every time you run out
Forget to reorder, and a dirty filter can drive up your energy bills.
Get 5% off every order, automatically
New filters arrive right when you need them
Pause, skip, or cancel anytime – no commitment needed.
