The Best Air Filters Delivered Right To Your Door
Get high quality replacement air filters delivered fast. Order the right size for you, with free shipping and the best prices on a huge selection of American made filters.
Shop Air Filters
Select your filter size
Select filter quality
MERV 13
“Covid Buster”
When should I change my furnace filter?
How Our Subscriptions Work
Choose a subscription and never have to order filters again!
Plus get free shipping on every order!
General FAQs
Q: How do I use FSTfiltration.com?
A: FST Filtration (fstfiltration.com) is a fast and simple way to order air filters. Just select the size and type of filter you need, and then choose how often you want them delivered to your home. We’ll ship the filters direct to your door, exactly when they need to be replaced. Air filters from FST are a similar or better quality than what you’d find at the big box stores, often at a fraction of the price.
Just visit fstfiltration.com and click “Find Your Filter”.
From there, select your filter size, your desired filter quality, and then choose whether you want to purchase one, or sign up for a subscription.
Q: How often do you really need to change your furnace filter?
A: A good rule of thumb is you should change your furnace filter every 60 days. If you have someone in the home with allergies or asthma, have pets, or live in a dusty environment, you may need to change your HVAC filter more often. Also factors like how much you’re using your heating or cooling system, the size of your home and your indoor air quality can determine how often your air filters should be changed.
Q: How much does a furnace filter cost?
A: HVAC filters, including furnace and AC filters, cost different amounts depending on the MERV rating and thickness of the filter itself. A thicker air filter has a higher cost, but delivers a better value since you don’t need to change it as often.
Q: How do I know what size filter to buy for my furnace?
A: FSTFiltration.com has a wide variety of replacement furnace air filter sizes, so the right size for you depends on your specific HVAC system.
Take a look at the existing filter inside your system to see what the dimensions are (they’re usually printed on the side of the filter). You can also determine the right size of air filter for your system by looking in your HVAC system’s owners manual.
If you need to measure your existing air filter:
- Measure the length (L) and the width (W).
- Measure the depth (D).
- Now combine these measurements as L x W x D.
Keep in mind that the filter’s true dimensions will be different than the manufacturer’s rounded numbers, which are called “nominal size”. For example, a filter may measure 19.5” x 19.5” x 2.5”, but be rounded by the manufacturer to 20” x 20” x 3”.
Shipping & Orders FAQs
Q: How are the replacement furnace air filters from FSTFiltration.com shipped?
A: Furnace air filters are shipped fast and free, via USPS Priority delivery.
Q: When will I receive my order?
A: We ship from Utah. Depending on your location, your filter should arrive within 2-8 days.
Q: What if I ordered the wrong filter?
A: Just give us a call at 435-637-3567 and we’ll help find a solution for you.
Q: What if my filter arrived damaged?
A: We’ll make it right! Give us a call at 435-637-3567.
Q: Can I return the filter?
A: We don’t accept returns, but we want to make sure that you’re happy. Give us a call at 435-637-3567 with any concerns or questions.
Q: I ordered a 4” filter, but received a 5” filter instead.
A: Did you receive a 5 inch air filter, but ordered a 4” inch filter? Don’t worry! You probably received an air filter with the “nominal size” label, which is different from the actual size.
Our manufacturer rounds up the last number (thickness). So when you order a 20x25x4 filter for example, what you will receive may actually measure 19-7/8″ x 24-7/8″ x 4-3/8″, but is labeled 20x25x5.
Try installing the filter you receive, but if for some reason it doesn’t fit, no worries! Just call 435-637-3567 and we’ll help you out.
Subscription FAQs
Q: Can I create more than one subscription?
A: Sure! If you have more than one property or home, you can create a subscription for each one. Just log into your account, click on “Subscriptions”, and start a new subscription with your same account.
Q: Can I change the frequency of delivery on my subscription?
A: Yes! If you need to change the delivery frequency on your subscription, email us at customerservice@fstsystems.com or call us at 435-637-3567 and we’ll take care of it for you.
Q: Can I change the filter size(s) associated with my subscription?
A: Absolutely! Just email us at customerservice@fstsystems.com or call us at 435-637-3567 and we’ll take care of it for you.