How do you filter your water while out hiking, trail running or adventuring away from treated water sources?

I’ve previously reviewed the SteriPen UV water treatment solution, which I love for its ease of use, but the Katadyn BeFree really does take easy to the next level. It’s no wonder to me that it has won numerous awards including the Runner’s World Gear of the Year Award. This is a seriously handy, straightforward piece of kit!

How does it work?

The Katadyn product video describes it as the “most compact, smash, dash and go” water filter and indeed, all you do is unscrew the cap and attached filter from the bottle; fill the soft flask with water; replace the cap and Bob’s your Uncle, you’re ready to drink.

If required, debris can simply be cleaned from the filter with some swishing around in the water; no back-flushing required. With its in built filter system (pore size of 0.1 micron ((0.0001 mm)), the BeFree meets “U.S. Environmental Protection Agency’s microbiological water purifier standards for reduction of bacteria (99.9999% Klebsiella terrigena) and protozoan cysts (99.9% Giardia and Cryptosporidium)”. Like anything of this nature, you do need to trust these claims if you’re going to use the product. I would say the biggest risk to it failing would be if you came into contact with untreated water on the flask itself if you were swishing it around in a dirty lake or stream or similar, and were infected from this, as opposed to any bacteria which has gone through the filter.

The reality for us using it this past week in New Zealand was that it was incredibly straightforward and a brilliant addition to our mountain hikes, especially with so much freshwater readily available.

routeburn track New Zealand katadyn

Refilling from a waterfall on Routeburn Track, New Zealand

Let’s go with the yeahs and mehs:


  • Compact and lightweight – approx 60g
  • Since this is a soft flask in itself, you essentially don’t need to carry an extra piece of kit as this doubles as filter and drinking vessel
  • Relatively wide mouthed for easy filling if you’re dunking in a lake or stream
  • I was impressed with the fast flow through the filter – not an issue at all for drinking, or for filling this flask and then decanting into others to share around the treated water
  • Incredibly portable. As you’ll know if you’ve read my article on soft flasks, I love to run and hike with soft flasks so this is a perfect combo for me. While empty it can be folded up and stashed away, and reduces in bulk as you drink
  • No need for batteries or power for water treatment
  • No need to wait for the water to be treated – just fill the flask and drink instantly treated water
  • Like the SteriPen, this brings environmental benefits – no need to buy plastic bottles of water while you’re out and about, assuming there’s a water source of some sort nearby
  • The Katadyn was an absolute gem on rainy New Zealand mountain hikes where waterfalls were flowing all over and meant for a worry free outing when it came to knowing we would have fresh water “on tap”! We also used it at DOC Huts to filter tap water and I’ll be using it for trail runs around the Sunshine Coast hinterland where untreated tank water is available at walkers camps
  • Incredibly simple to use!


  • Can only treat 600ml of water at one time and need to squeeze this through the filter for treatment. This makes it more suited to single person use. However, Katadyn notified me via Instagram (thanks!) that they do offer larger solutions too including a 1L and a 3L bottle
  • This filter will not defend against viruses, so if you are travelling somewhere where this is an issue, I would definitely consider an alternative like the SteriPen Ultra
  • I did find the cap a little leaky if not screwed on in a particular way – especially when squeezing the flask hard to decant water into other bottles
  • I wouldn’t use this in anything worse than cloudy water as the filter may get too clogged (although I haven’t tried and tested this)
  • The flask itself is a soft Hydrapak flask, which have the potential to split, although this particular flask feels slightly thicker (perhaps?!) than the usual Salomon flasks. I’m not sure if there’s a flask replacement option from Katadyn if you do have an issue? The product does come with a two year warranty
  • The filter is useable for 1000 litres of water although Katadyn mentions this does depend on water quality. I have no idea how I’ll know when I’ve reached this point and whether the filter is still being effective!

Lake Mackenzie, Routeburn Track, New Zealand

katadyn be free routeburn track NZ

As an aside, this isn’t a direct criticism of the Katadyn, but I was using the BeFree with my Salomon Peak 30 fast packing backpack (pictured) and when the flask was full, it was too bulky to fit into the bottle holder at the front of the pack. I ended up decanting water from it into my smaller Salomon flasks each time, which didn’t take too much extra time.

In summary, I would give the Katadyn a definite 5 stars for its absolute ease of use; its two in one bottle/filter combo and its collapsible, lightweight nature. Although we also carried the SteriPen on our New Zealand hikes last week, we ended up mainly just using the Katadyn BeFree. There’s no doubt I’ll be grabbing this to take on camping/hiking trips from now on and for longer trail runs out in the bush.

Winner winner.

Milford sound sea kayak

BeFree soft flask tucked under the bungee of a sea kayak deck on Milford Sound, NZ

Have you used the Katadyn BeFree? What’s your preferred approach to water treatment while adventuring outdoors? I would love to hear from you!

As always, this product was independently purchased by me ($69.95 AUD), with no input whatsoever from the brand.