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Trane Perfect Fit 5" AC & Furnace Filters
The original Trane Perfect Fit filters, in stock and ready to ship. These 5-inch pleated filters carry a MERV 8 rating and trap far more dust, pollen, and bacteria than a standard filter. Perfect Fit comes two ways: an exact size, or an expandable that stretches to fit. Can't find your size? We also make custom filters
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Choose Your Trane Perfect Fit Filter Size
Standard (above)
Comes in a set size. Match the size on your old filter and you are done. This is what most people buy. If your size is in the list above, get the standard.
Expandable (below)
Stretches accordion-style to fit odd sizes you cannot get as a standard. Trane makes two: a wide one and a narrow one. If your size is not above, one of these will fit.
Trane Perfect Fit Expandable
Note: the 27-1/4 and 25 are the same wide filter (BAYFTFREXM2) at two expansion sizes. The 21-1/8 is the narrow one (BAYFTAHEXM2).
Not sure which size or type?
📞 954-588-7774Real people answer. We will match your exact filter in about a minute.
What is a Trane Perfect Fit filter?
A Trane Perfect Fit filter is a 5-inch pleated media filter that slides into a filter cabinet next to your Trane or American Standard furnace or air handler. It carries a MERV 8 rating, which handles everyday dust, lint, and pollen, and it lasts far longer than a thin 1-inch filter. Each one is sold as a 2-pack with free shipping. Most people know these by their part numbers, which start with BAYFT or FLR, like BAYFTAH23M, BAYFTFR21M, or FLR06073. The BAYFT number is the filter and the FLR number is the cabinet it fits, so you will often see both. You may also hear these called Trane AC filters, air conditioner filters, or furnace filters. They trap far more dust, pollen, and bacteria than a typical filter, filtering up to 15 times better than a standard 1-inch filter.
What size Trane filter do I need?
There are three easy ways to find your size. First, read the measurements printed on the cardboard edge of your old filter, for example 21 x 23.5 x 5 or 24.5 x 27 x 5, and match it to the list above. Second, check the label on your filter cabinet door, which often lists the part number. Third, if you only know your furnace model, like an XR95, XV80, or XL80, call us at 954-588-7774 and a real person will match it in about a minute. If your size is not in the standard list, the expandable filter further down stretches to fit.
How to read a Trane part number
Trane part numbers look confusing but they follow a simple pattern. Take BAYFTAH23M. The middle letters, AH, FR, or DN, tell you which cabinet it fits. The number, 23, is a size code, not the actual inches. The M means it is a media filter. Cabinet width is the key: a 21-inch cabinet uses an AH-size filter about 20 inches wide, a 24.5-inch cabinet uses an FR-size filter about 26 inches wide, and a 17.5-inch cabinet uses the smaller DN size. When in doubt, go by the size printed on your old filter, not the furnace model.
Find your filter by Trane furnace model
Your Trane model is on the sticker inside the unit. Premium furnaces like the XV, XC, and XLi series and air handlers like the TEM series use a 5-inch Perfect Fit media filter. Mid-range XR and XT models use the same. Older or value models like the XB and XE may use a standard 1-inch return filter instead, if there is no media cabinet installed. One important note: the furnace model alone does not lock in the filter size, because the size comes from the filter cabinet, not the furnace. Two homes with the same furnace can take different filters. So always confirm with the size on your old filter, the label on the cabinet, or a quick call to us.
Standard vs Expandable Perfect Fit
Both are the same Perfect Fit filter and do the same job. The standard filter comes in one fixed size, so you match your size and you are done. The expandable filter stretches accordion-style to fit odd or hard-to-find sizes that are not offered as a standard. Trane makes just two expandable models: a wide one, BAYFTFREXM2, and a narrow one, BAYFTAHEXM2. If your size is in the standard list above, buy the standard. If it is not, the expandable will fit.
Want cleaner air? MERV 8 vs MERV 11
The standard Perfect Fit is MERV 8, which is the right choice for most homes and captures everyday dust and lint. If you have pets, allergies, or want to catch finer particles, Trane also makes a higher grade version, the QuikBox, in MERV 11 and MERV 13. It fits the same way and simply filters more. Call us if you would like help choosing the right level for your home.
How often should I change a Trane Perfect Fit filter?
Because Perfect Fit filters are a full 5 inches thick, they hold a lot more dust than a thin filter and do not need changing as often. Plan on every 6 to 12 months for most homes. If you have pets, smokers, or heavy dust, change on the shorter end, closer to every 6 months. A good habit is to check it when the seasons change.
Are Trane and American Standard filters the same?
Yes. Trane and American Standard are built by the same company and use the exact same filter systems, so the same part numbers fit both. If you have an American Standard furnace, these Perfect Fit filters are the correct replacement.
Why can't I find these at the hardware store?
Trane Perfect Fit filters use their own sizes that are not the standard 16x25x1 you find on a store shelf, so hardware stores rarely carry them. That is exactly why we stock the full Trane line, ship free, and have real people on the phone to make sure you get the right one the first time.
