One of the most popular under-the-sink water filters of the past decade has been the 3US-MAX-S01 from 3M. This sub-$100 filter was known for its excellent performance and ease of installation and, when paired with the Filtrete 3US-MAX-F01 Maximum filter, it was able to remove over 99% of lead from your water.
The problem is that the Filtrete 3US-MAX-F01 Maximum replacement filter has gotten quite hard to find. So hard in fact that it’s not clear if it’s even practical to keep the 3US-MAX-S01 filter system. So does 3M still make the Maximum filter?
3US-MAX-S01 vs. 3US-PF01
When buying your replacement filter, you’ll want to make sure you get the Maximum model, not the Advanced model. The Maximum is a little more expensive but it’s the only model that removes lead from water. The Advanced will improve the taste of your water and remove some unwanted matter, but it’s not certified by the NSF for lead removal.
The point of this article is that the the Max — specifically the Filtrete 3US-MAX-F01 Maximum Under Sink Quick Change Water Filtration Replacement Filter — has gotten incredibly hard to find and it’s becoming a problem for 3M filter owners. The fact that you can still find the Advanced model for sale isn’t much help if you are concerned about lead your water.
Buying The Filtrete 3US-MAX-F01
If you’re goal is to get an official 3M Filtrete filter than your options are limited to:
- Best Buy
- Marketplace sells on Walmart, Amazon, Home Depot, eBay
As of December 2023 these seller are almost entirely sold out. You might find a unit or two available from a 3rd party (marketplace) seller on Amazon, but you’ll be paying a hefty premium, often close to $55 for a filter that used to sell for about $35.
Don’t be deceived about availability though, as you will be able to find the listings when searching, but most are sold out. Or the filter is in stock, but only available locally, for instance at a Walmart store that won’t ship to buyers.
WaterDrop 3US-MAX-F01 Maximum
Water filter brand WaterDrop now also makes a replacement filter for Filtrete systems. Their model is also called the 3US-MAX-F01 Maximum and it’s sold via Amazon and a few other sellers.
WaterDrop is well known for its refrigerator water filters as well as the company making lower priced versions of popular filter replacements, as is the case here. It’s not clear if this is an official replacement done in partnership with 3M, but based on their us of the 3M model name and their claiming the filters passing NSF 42 certification, they seem to be official.
There are other brands that make 3M replacement filters, like AquaCrest and Filter Logic, but they seem to focus on the Advanced model (3US-PF01), which isn’t certified for lead removal.
Buy Another 3US-MAX-S01
It’s expensive and wasteful, but one thing you can do to get another replacement filter is to simply buy the entire system again. This will cost you about $60-$80, but you will get another 3US-MAX-F01 if you buy an entire 3US-MAX-S01 system. You’ll also get a bunch of replacement parts you don’t need, but they might be nice to have as a backup.
This option is only useful if a) you are desperate because your current filter is running slowly b) you find a great deal on the 3US-MAX-S01. Finding a deal is entirely possible as the 3US-MAX-S01 seems to be being phased out by 3M as newer filter designs with better certifications — like NSF/ANSI 53 which also blocks PFAS — are becoming increasingly popular.
So Is The 3US-MAX-F01 Still Made?
There is no official word on this, but it seems like no, it’s not longer actively being made by 3M and they have outsourced manufacturing of this replacement filter to the WaterDrop brand. That said there seems to be no official communication or press release on the matter, so this is simply our best guess based on extensive research into the filter (which we’ve actively used for about 5 years now).