Best Water Filters for Trail Running of 2023


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Apr 05, 2024

Best Water Filters for Trail Running of 2023

Check out iRunFar’s picks for the best water purification devices for trail runners and ultrarunners. iRunFar’s Meghan Hicks uses the Katadyn BeFree 0.6L to filter water from a stream in Colorado. We

Check out iRunFar’s picks for the best water purification devices for trail runners and ultrarunners.

iRunFar’s Meghan Hicks uses the Katadyn BeFree 0.6L to filter water from a stream in Colorado. We awarded this the best overall filter for trail runners. Photo: iRunFar/Eszter Horanyi

Numerous water purification methods can suit various needs and hydration preferences, but choosing the best water filter for trail running requires a few special considerations. Filters that have built-in flasks allow for easy water filtration on the go. Some filters work better for bladders than handheld bottles or small soft flasks. Some options are best for individual use, while others are ideal for a small group refilling together.

Certain methods work best for clear-flowing mountain streams that we runners constantly seek, while other systems, or combinations of them, can purify the most unappealing water sources.

To help you choose the best system for your needs, we researched the world of water purification and tested the best options for trail running. For more background information about water purification for trail running, see our glossary, buying advice, testing methodology, and frequently asked questions.

Melissa Beaury (left) and iRunFar’s Meghan Hicks fastpacking in Utah’s canyon country. Meghan is carrying a Katadyn BeFree 0.6L in this image. Photo: iRunFar/Eszter Horanyi



There’s a good reason the Katadyn BeFree 0.6L is wildly popular among trail runners. It’s small, lightweight, compact, and reliable. The filter and soft flask weigh just 59 grams and measure about 4.3 inches in length, including the lid. The soft flask of this filter can easily fit in the palm of your hand — and in the pocket of a hydration vest.

The ease of use of this filter also sets it apart from its competitors. To operate, unscrew and remove the lid containing the filter, and fill the soft flask with water. Clear running water is generally the best option if available. Then, screw the lid back on and drink through the water bottle mouthpiece! If you want to refill additional water containers, turn it upside down, and the water will flow on its own, or you can squeeze the soft flask to help push the water through the filter more quickly.

It only takes a minute to filter two liters, though this flow rate will slow over time as the filter becomes clogged. The filter is easy to clean in the field if it becomes clogged — no backwashing or extra tools are needed; just swish or shake the bottle with clean water.

To learn more, check out our in-depth Katadyn BeFree 0.6L review.

Effective at Removing: Bacteria, cysts, and sediment with its filter pore size of 0.1 micrometers (0.0001mm)



With a similar design and operation to our other top choices, the LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter receives the runner-up award when it comes to water purification for trail runners. At 102 grams, the extra bulk and weight, when compared to other similar filters, are the only things that put this option lower on the list of favorites. The filter and lid together are 5.1 inches in length, so it will still fit easily into a hydration vest, but it’s not the most compact option available. That said, the filter can be unscrewed and removed from the lid, making the whole system more packable.

The bottle material feels thicker than comparable soft flasks, which indicates that it’s durable — yet it still packs down to about the size of a fist. In addition, the filter is housed in a plastic case, which adds weight but increases the protection of the filter’s delicate fibers.

Because the 650-milliliter soft flask is dark, it’s tricky to see how much water is in the bottle unless you hold it up to the light. If you’re drinking straight from the bottle, it may not be apparent when running low on water. However, because of the bottle’s size and shape, trail runners will be likelier to use this filter and bottle to refill other water bottles. In this case, its high flow rate and ease of use make it a great choice.

Read more in our in-depth LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter review.

Effective at Removing: Bacteria, parasites, microplastics, silt, sand, and cloudiness with a filter pore size of 0.2 micrometers (0.0002mm)



Although it has some limitations, the Salomon Soft Flask XA Filter 490ml/16oz 42 is an excellent water filter for trail runners. At 52 grams, it’s slightly lighter than the Katadyn BeFree 0.6L, though its soft flask holds only 490 milliliters rather than 600 milliliters of liquid. Its long cylindrical shape is designed to fit Salomon vests and will fit into the front pocket of most hydration vests. The hollow fiber filter is about 4.5 inches long, and — fun fact — since both this filter and the Katadyn BeFree 0.6L filter are designed to fit a HydraPak soft flask’s threads, either filter will work with most HydraPak soft flasks, excluding those with a narrow mouth opening.

The hard plastic loop on the filter makes it easier to hold while filling it up and putting the lid back on. To operate the filter, simply fill the soft flask with water and either drink from the mouthpiece on the lid or squeeze the mouthpiece with your fingers and filter the water into another container. The filter has a high flow rate, which makes the whole process quick.

The only real downside of this filter is that the nozzle has no cover to protect it from the accidental splashing of contaminated water, like most of the other filters in this guide. Additionally, you must place your potentially dirty fingers on the mouthpiece if you want to refill additional water bottles. This adds a risk of contamination unless you disinfect your hands first.

Effective at Removing: Bacteria and protozoa



While we generally didn’t consider pump filters in our “best for trail running” water purification testing and guide, we made an exception for the MSR TrailShot Pocket-Sized Water Filter. This unique filter is compact, versatile, effective, and small enough for trail runners to carry. It can be used to drink directly from a creek or to refill water vessels on the go. And its design makes it practical for filtering shallow water, which is a huge plus if you’re venturing into the alpine, where your water source might be a small, babbling stream. In addition, this aptly named filter can indeed fit easily into a hydration vest pocket. Like our other favorite water filters for trail running, it doesn’t require additional tools for cleaning — a few shakes will clear up a clogged filter and restore flow.

This filter is heavier, at 142 grams than other filters designed for trail running. It also doesn’t work as a water bottle, which adds an additional weight penalty to the whole system since you’ll have to carry a bottle to filter into unless you’re running from water source to water source without carrying water. However, it’s quick to deploy without taking any lids on or off or screwing together any parts — simply pull it out of your pocket, drop the filter end into the cleanest water available, and give the little bottle some squeezes.

Depending on your hand and forearm strength, it can filter a liter of water in about 60 seconds. In testing, we found that it’s an ideal filter for refilling larger containers, like a one- to two-liter water bladder. It’s also a good filter option for group use since it’s quick to deploy and easy to operate.

Effective at Removing: Bacteria, protozoa, and sediment with a filter pore size of 0.2 micrometers (0.0002mm)



Water filters are a common solution for removing bacteria, protozoa, and sediment from water, but a purifier like the SteriPen Ultralight UV Water Purifier will inactivate all three classes of microorganisms: bacteria, protozoa, and viruses. It does so by using ultraviolet light to scramble the DNA of microorganisms in the water so that they cannot embed in your digestive system and reproduce, which is how they make you sick. This device is incredibly light and compact at just 76 grams and measures 5.1 inches in length. It’s comparable in size to a granola bar you might carry in your hydration vest. It’s also fast and can treat one liter of water in 90 seconds.

This device is simple and easy to use. Simply dip it into your water vessel so that the two metal sensors are submerged, then stir it slowly until the blinking green light turns solid green. The purifier will blink red and green when the battery is getting low, and since it’s rechargeable, all you need to do is plug it in before your next run so that it’s fully charged. A single charge will treat up to 20 liters of water, and the device will hold its charge for months.

This water purifier does have a few key limitations. For one, it requires clear water to be effective. This probably isn’t an issue if you’re running among fresh snowmelt runoff in the alpine — however, if your water source is cloudy or murky, you’ll need to pre-filter the water.

In addition, since it’s essentially a small lamp, you’ll want to be careful not to drop it — it will break more easily than other purifiers. It also won’t work with small water bottles that don’t have a wide enough opening to allow stirring. Instead, this is ideal for individuals using a one-liter bladder or similar.

Effective at Removing: Bacteria, protozoa, cysts, and viruses using ultraviolet light



If you’re trail running with friends and want to carry one filter for the group, we recommend using the Platypus QuickDraw Microfilter System. The filtration system has a sturdy yet collapsible one-liter water bag and a separate hollow fiber filter enclosed in a protective case. When it’s time to refill, fill the water bag from your nearest water source. After attaching the filter, turn it upside down and squeeze the bag to help the water flow through the filter and into your water bottles or hydration reservoir. Be careful not to lose the small protective caps during the refilling process. Although it’s also possible to drink directly from the filter, this would not be practical while trail running since the water bag holds a full liter and would be cumbersome to carry by hand.

The high flow rate of 20 seconds per liter makes this an excellent choice when you have to filter a lot of water at once. At 95 grams, it’s not the lightest system, though its multiple parts break down, and the water bag rolls up to make it more packable. You’ll also most likely have to carry a second bottle that is easier to drink from while running when using this system. While it’s not the most compact and ultralight option available, the main draw of this system is its speedy filter rate. That’s why it’s an excellent option for a group — you can refill everyone’s bottles and reservoirs easily in minutes.

Effective at Removing: Bacteria, protozoa, and particulate with its filter pore size of 0.2 micrometers (0.0002mm)



While plenty of great water filters and purifiers are available, carrying a chemical backup option, such as Aquatabs 8.5mg Tablets X30 is always good. These inexpensive tablets, which use sodium dichloroisocyanurate as the active ingredient, come in a pack of 30, and a single tablet can treat up to two quarts (1.89 liters) of clear water. A single tablet can also treat half as much cloudy water, though heavily sedimented water should be pre-filtered. Unlike other chemical water treatments, such as iodine, these tablets don’t change the taste or color of the water. Even if you’re not planning on picking up extra water on your run, it’s not a bad idea to carry a few of these tablets whenever you head out, just in case something goes wrong and you need extra drinking water.

These tablets are effective against bacteria, protozoa, and viruses. The only exception is the protozoa cryptosporidium — you’d need a filter or additional treatment to inactivate them. In addition, this treatment method won’t remove dirt, bits of moss, or other sediment — so it’s better for use with clear water. Finally, the tablets take about 30 minutes to treat your water, so if you use this method while trail running, you’ll want to set a timer before sipping.

Effective at Removing: Protozoa, bacteria, cysts, and viruses using sodium dichloroisocyanurate



We love the Sawyer Mini Water Filtration System for trail running because it’s inexpensive, easy to use, and ultra-lightweight. At just 40 grams, it’s one of the lightest filtration systems on the market and the lightest in this guide. It’s also the least expensive, and at one point, it was probably one of the most popular water filtration systems among trail runners. Even with many other options, this filtration system remains a favorite for trail runners and through hikers.

This system comes with a lightweight 16-ounce water bag and a small filter that measures 5.3 inches in length. To use, simply fill the bag with water, screw the filter onto the opening, turn the system upside down, and squeeze the bag. The filtered water will flow into your water bottle, reservoir, or mouth. While the system is straightforward, the bag also contains step-by-step instructions in case you forget. If the filter slows down or gets clogged, you can clean it by using the included syringe to backwash the filter, essentially pushing water backward through the filter to push gunk away from the fiber pores.

Effective at Removing: Bacteria, protozoa, and microplastics with its filter pore size of 0.1 micrometers (0.0001mm)

Water Filter: A water filter acts as a sieve for particles in the water and effectively removes bacteria, protozoa, microplastics, sediment, and other particulate matter.

Water Purifier: A water purifier effectively inactivates all three classes of microbes: protozoa, bacteria, and viruses. Water purification uses ultraviolet light or chemicals to render microorganisms harmless.

Testing the LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter in some spring runoff in Colorado. Photo: iRunFar/Eszter Horanyi

Sodium Dichloroisocyanurate: Sodium dichloroisocyanurate is a colorless, water-soluble chemical comprising sodium, chlorine, carbon, nitrogen, oxygen, and hydrogen. It is a disinfectant for water purification and is the active ingredient in Aquatabs 8.5mg Tablets X30. It is effective against the giardia parasite but not cryptosporidium.

Bacteria: Bacteria are microscopic single-celled organisms found almost everywhere. While bacteria are vital to the planet’s ecosystems, certain types are harmful or deadly to humans. Escherichia coli (E. coli), Campylobacter jejuni, and Salmonella are some harmful bacteria found in water.

Protozoa: Protozoa are single-celled organisms that can be free-living or parasitic and exist in most habitats worldwide. Giardia lamblia and Cryptosporidium are two parasitic protozoa found in water that can harm humans.

Virus: Waterborne viruses that infect humans come from human and animal feces in the water. The two most common waterborne viruses in North America are the rotavirus and the norovirus, which cause fever, vomiting, and diarrhea. In other parts of the world, other types of viruses may be more common in backcountry waters.

Cryptosporidium: Cryptosporidium is a microscopic parasite that causes the diarrheal disease cryptosporidiosis. Both drinking and recreational water is the most common way the parasite spreads. Due to its outer shell, “crypto” can survive for long periods outside a host body and tolerate chlorine disinfection.

Water Purification: Filter Versus Treatment

A water filter is essentially a strainer with microscopic pores that removes sediment, microplastics, and microbes such as bacteria and protozoa from water. The smaller a water filter’s pore size, the more matter it will remove from the water. When choosing the best water filter for trail running, you’ll want to select one with a pore size of either 0.1 or 0.2 micrometers.

Because viruses are so tiny, they are generally not captured in a filter and must be deactivated or killed by another purification method. Eventually, a water filter’s pores will become clogged, and the filter will need to be cleaned or replaced. We found the best water filter for trail runners is the Katadyn BeFree 0.6L because of its light weight and ease of use.

The Katadyn BeFree 0.6L is our favorite filter for trail runners because it combines the ability to filter water with an easy-to-use soft flask. Photo: iRunFar/Meghan Hicks

Water purifiers are required to meet federal standards for the inactivation of all three classes of microbes: protozoa, bacteria, and viruses. The SteriPen Ultralight UV Water Purifier is an example of using ultraviolet light to purify water. Other common purification methods include chemicals such as iodine, chlorine, or chlorine dioxide.

For trail runners, a water filter will be sufficient for most scenarios. However, if you’re running in an area where waterborne viruses are a risk, or you want added confidence in the safety of your drinking water, you could filter water and then treat it with one of the purification methods listed above.

Water Filter Pore Size

Water filters have microscopic pores that only allow the tiniest particles through. Larger particles, such as bacteria and protozoa, will get caught in the filter’s fibers. The smaller the pore size, the more the filter will catch and eliminate from your drinking water. That said, smaller pores will also clog more quickly, requiring more frequent cleaning and filter replacement. Filtering from the cleanest possible water sources will help prolong the life of your filter.

All the filters on our list have a pore size of 0.1 or 0.2 micrometers. A micrometer, often abbreviated as a micron, is one-millionth of a meter. There are 1,000 micrometers in a millimeter and 10,000 micrometers in a centimeter. For reference, the smallest objects visible to the naked eye are 40 to 50 micrometers.

So, yeah, these water filter pores are tiny! Small enough, in fact, to catch 99.9999% of bacteria and 99.99% of protozoa. Amazingly, viruses are even smaller than these organisms and can still make it through a water filter’s pores, which is why we rely on additional purification methods like Aquatabs 8.5mg Tablets X30 to inactivate viruses in our water.

Backwashing and Cleaning a Water Filter

Some water filters require periodic backwashing or other types of cleaning to help maintain a high flow rate. Backwashing is pushing water backward through a filter to clear out the gunk clogging the pores.

Some filters, such as the LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter and the Sawyer Mini Water Filtration System, come with a syringe for backwashing the filter.

For other filters, like the Platypus QuickDraw Microfilter System, there are two methods for cleaning the filter, shaking or backwashing, that don’t require a syringe. Others, including the MSR TrailShot Pocket-Sized Water Filter and the Katadyn BeFree 0.6L, can be easily cleaned at home or in the field with a shake or swish method.

It’s important to note that filters and the cartridges they’re housed in are delicate, and cleaning them improperly can cause permanent damage. For best results, we recommend following the instructions in the user manual with your water filter.

Water Filter Storage and Care

For the best water filter storage and care, it’s important to follow the manufacturer’s instructions about your specific water filter. Before putting your filter into long-term storage, you’ll want to clean it first and allow it to dry completely. Store your filter away from direct sunlight and in a location where it won’t freeze.

LifeStraw recommends storing the LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter in a saline solution made by mixing salt with water. The solution helps maintain the filter membrane’s hydrophilic properties while preventing mold and algae growth. Caring for your filter through proper cleaning and storage will help maintain its performance and extend its life.

Early season fastpacking in Colorado means you’ll want to carry a good way to purify your water. Photo: iRunFar/Eszter Horanyi

The iRunFar team is composed of road runners, trail runners, and ultrarunners with a collective 150-plus years of running experience. Several team members have been traveling in the backcountry and using water purification methods for over two decades.

We started this buyer’s guide with a deep dive into the water purification and treatment marketplace and the team’s previous experience and preferences with water purification methodology, narrowing our choices down to a list of the best water filters for trail running.

From there, author Alli Hartz took our top choices into the field, where she tested carrying and using them while running. Because this testing period overlapped with her trip to Ecuador, Alli tested a few of the filters in the waters near Quito and Cotopaxi National Park. The rest were tested along her home trails in central Oregon. This guide is a roundup of the top performers.

Please note that product models are routinely discontinued in the outdoor gear world, while new ones frequently come to market. At the same time, we here at iRunFar often keep using our top picks in our daily running … they’re our top picks, after all! Sometimes that continued use results in uncovering product failures. With all this — product discontinuations, product introductions, and product failures — in mind, we routinely update our buyer’s guides based on past and ongoing testing and research by our authors and editorial team. While these updates can appear to be us pushing the newest product, it’s anything but that. When we update any buyer’s guide, most products will likely remain the same. That matches our goal: to get you in the best gear you’ll be using for a long time.

Why do you need purified water while trail running?

If it’s unclear from our glossary section above, there are some nasty types of bacteria, protozoa, and other organisms in lakes, rivers, streams, cow tanks, and puddles that can be harmful and even deadly to humans. The most common risk from drinking untreated water is some sort of bacterial or viral infection that will make you very sick — causing things like diarrhea, vomiting, headaches, and fever — which is certainly not a fun post-running experience and can lead to even less fun things like going to the hospital, experiencing long-term health effects, or dying.

While those cascading mountain streams and turquoise alpine lakes may appear innocuous, the fact is that any water source that has animal life nearby can contain microscopic organisms that can make humans very sick. Purifying water before drinking eliminates nearly all harmful substances and significantly reduces the risk of getting sick. Plus, water filters will catch dirt, tiny bits of moss, and other particulates so that your water tastes as pure as that mountain stream looks. And when the best water filters for trail running options are as light, fast, and as easy to use as the Katadyn BeFree 0.6L, there’s no reason not to carry one.

Meghan Hicks of iRunFar tests the LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with Filter on a spring mountain run. Photo: iRunFar/Eszter Horanyi

What type of water purifier is best for trail running?

The best purifier for trail runners is lightweight, compact, effective, easy to use, and quick. During long days on the trail, stopping to filter water can gobble up precious daylight — especially if it requires getting off the trail to access a good water source. Therefore, a water filter or purifier that’s easy to access and deploy is ideal.

This could be a filter that doubles as a water bottle, like the Katadyn BeFree 0.6L or the Salomon Soft Flask XA Filter 490ml/16oz 42.

For runners who prefer to run with a hydration bladder, the Sawyer Mini Water Filtration System may be a good option since it’s super lightweight and can be used in line with a hydration bladder hose.

Or, if you know you’ll be near clear water, you may opt for SteriPen Ultralight UV Water Purifier, as it’s so lightweight, small, and quick.

When choosing the best water purification system, consider how you prefer to drink water on the trail — from small, soft flasks or a bladder with a hose. Next, consider how you’ll carry the filter or purifier and what seems the most comfortable and convenient. Finally, consider which tool seems easy and intuitive to you.

While all the filters or purifiers on this list are relatively easy to use, some have more parts or require more steps to use. If you’re notorious for misplacing small components, opt for one that doesn’t have detachable parts. There are many good options for the best water filter for trail running out there, so once you’ve narrowed it down, go with your gut!

How safe are water filters for trail running?

Since water filters eliminate 99.9999% of bacteria and 99.99% of protozoa, they make water very safe to drink. The only microorganisms they don’t effectively remove are viruses. If you’re filtering water in an area with harmful viruses, then it’s a good idea to use a backup option like the SteriPen Ultralight UV Water Purifier.

Being able to filter from wild water sources while fastpacking is important. Photo: iRunFar/Eszter Horanyi

What is the most effective water filter for trail running?

While there are no federal regulations for backcountry water filters, there are protocols and guidelines that filters should, and typically do, meet. You might find phrases like “meets NSF Protocol P231” and/or “the U.S. Environmental Protection Agency’s Guide Standard and Protocol for Testing Microbiological Purifiers” on the water filter’s informational materials.

In addition, you’ll likely see specific claims, such as “removes 99.9999% of bacteria and 99.99% of protozoa.” This type of language indicates that the water filter is appropriate for the backcountry. Other numbers worth paying attention to are the filter’s pore size, which should be 0.1 or 0.2 micrometers — small enough to filter out bacteria and protozoa. All the filters on our list meet these standards and are adequate and appropriate for trail running.

Aside from these minimum standards, the best water filter for trail running will be compact, comfortable to carry, easy to use, and durable. These factors will ensure you carry and use your filter and don’t risk drinking straight from backcountry waterways. Pairing a water filter like the Salomon Soft Flask XA Filter 490ml/16oz 42 with a water purification method like the SteriPen Ultralight UV Water Purifier will all but ensure that your water is safe to drink wherever you’re picking it up from.

How much water should I carry on a trail run?

This is a question that will depend on many factors as well as individual preferences. When planning for a long day on the trail and determining how much water to carry, the weather and how much water you’ll have access to on your route are two of the biggest variables to consider. You’ll need more water on a hot, dry day than on a chilly or rainy day.

At the same time, carrying a liter or more of water can feel heavy while running, so if you know you’ll have access to plenty of water, it may be worth carrying less and planning to stop and filter. That said, filtering takes time and breaks up the flow of the run.

After weighing all these factors, it’s a good idea to err on the conservative side and carry a bit more water than you think you’ll need, as well as a filter in case you run out. The consequences of getting dehydrated or drinking unfiltered water are much worse than the burden of carrying a few extra ounces on your run. Having a sleeve of Aquatabs 8.5mg Tablets X30 in your pack at all times can provide a safety backup in case something goes wrong and you run out of water unexpectedly.

This fastpacking campsite looks glorious at sunset. Fastpacking trail runners should consider their best means of water purification in the backcountry. Photo: iRunFar/Eszter Horanyi

How do you know when it’s time to replace a water filter?

A few clues will help you determine when it’s time to replace your filter. The biggest one will be when the flow rate slows to an unbearable rate. The longevity of your filter will depend on the type of water you’re filtering.

However, don’t toss your filter just because it’s starting to slow down — try cleaning it or backwashing it first. Cleaning the filter of the Katadyn BeFree 0.6L regularly can keep it flowing efficiently for many liters of water. Your filter’s user manual will be a good reference for the best way to clean it. If you’ve made some solid attempts at cleaning it and it’s still slow — and maybe you know you’ve been filtering some mucky water — then it may be time to consider replacing your filter. Depending on the model of your water filter, you may be able to replace the filter cartridge rather than the entire system.

Does altitude affect water filter flow rates?

Yes! Water filter flow rates tend to be slower at higher altitudes. If you’re heading up high, be sure your filter is clean and in good working condition before you go. It’s also always a good idea to have a backup water purification method, like Aquatabs 8.5mg Tablets X30, in case something happens with your filter.

Can my water filter be frozen?

Freezing will damage most water filters, making them less effective. Give your filter’s user manual a careful read to see how freezing could affect its performance. For trail running, a frozen water filter is rarely going to be an issue. If you’re concerned about your filter freezing, consider carrying it close to your core and bringing a backup purification method, such as Aquatabs 8.5mg Tablets X30.

Meghan Hicks of iRunFar carries a Katadyn BeFree 0.6L during a fastpacking trip in the San Juan Mountains of Colorado. Photo: iRunFar/Eszter Horanyi

Can my water filter withstand being dropped?

Generally, water filters are fragile and can be damaged by a hard drop. If you suspect you may have damaged your filter, look at the user manual — most have instructions for testing the integrity of your filter. That way, you’ll know for sure that it’s working properly before heading back into the field with it. The SteriPen Ultralight UV Water Purifier is especially fragile and needs to be treated with care.

How durable are the water filter flasks?

Most of the flasks that come with water filters are comparable to the flasks made by regular running brands. They can withstand the regular wear and tear of being in a running vest or fastpacking pack pocket, but they will spring leaks on occasion. Many of the filters included in this guide, including the Katadyn BeFree 0.6L, will screw onto any HydraPak soft flask if the original one gets damaged.

We want to hear about your favorite water purifier for trail running! Leave a comment to share which filter or treatment system you love, and be sure to tell us in what conditions it performs best for you.

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Alli Hartz is a member of the gear review team at iRunFar. She’s been writing about outdoor gear, outdoor adventure, and adventure travel for 10 years. Aside from iRunFar, Alli contributes gear reviews and adventure stories to Switchback Travel, Travel Oregon, and other outlets. She also works as a ski guide during the winter season and has dabbled in run-skiing on the Cascade volcanoes. Alli is based in Bend, Oregon, where she loves to run from her front door up into the Three Sisters Wilderness.

Eszter Horanyi identifies as a Runner Under Duress, in that she’ll run if it gets her deep into the mountains or canyons faster than walking would, but she’ll most likely complain about it. A retired long-distance bike racer, she gave ultra foot racing a go and finished the Ouray 100 in 2017, but ultimately decided that she prefers a slower pace of life of taking photos during long days in the mountains and smelling the flowers while being outside for as many hours of the day as possible. Eszter will take any opportunity to go adventuring in the mountains or desert by foot, bike, or boat, and has lived the digital nomad lifestyle throughout the west for the past seven years.

Overall Best Water Filter for Trail RunningKatadyn BeFree 0.6LOverall Best Water Filter for Trail Running – Runner-Up: LifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with FilterOverall Best Water Filter for Trail Running – Runner-Up: Salomon Soft Flask XA Filter 490ml/16oz 42Best Water Filter for use with BladdersMSR TrailShot Pocket-Sized Water FilterBest Water PurifierSteriPen Ultralight UV Water PurifierBest Water Filter For Trail Running for Group UsePlatypus QuickDraw Microfilter SystemBest Backup Water TreatmentAquatabs 8.5mg Tablets X30Best Budget Water Filter for Trail RunningSawyer Mini Water Filtration SystemProsConsKatadyn BeFree 0.6LEffective at RemovingProsConsLifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with FilterEffective at RemovingProsConsSalomon Soft Flask XA Filter 490ml/16oz 42Effective at RemovingProsConsMSR TrailShot Pocket-Sized Water FilterEffective at RemovingProsConsSteriPen Ultralight UV Water PurifierEffective at Removing ProsConsPlatypus QuickDraw Microfilter SystemEffective at RemovingProsConsAquatabs 8.5mg Tablets X30Effective at RemovingProsConsSawyer Mini Water Filtration SystemEffective at RemovingWater FilterWater PurifierSodium DichloroisocyanurateAquatabs 8.5mg Tablets X30BacteriaProtozoaVirusCryptosporidiumWater Purification: Filter Versus TreatmentKatadyn BeFree 0.6LSteriPen Ultralight UV Water PurifierWater Filter Pore SizeAquatabs 8.5mg Tablets X30Backwashing and Cleaning a Water FilterLifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with FilterSawyer Mini Water Filtration SystemPlatypus QuickDraw Microfilter SystemMSR TrailShot Pocket-Sized Water FilterKatadyn BeFree 0.6LWater Filter Storage and CareLifeStraw Peak Series Collapsible Squeeze 650 ml Bottle with FilterWhy do you need purified water while trail running? Katadyn BeFree 0.6LWhat type of water purifier is best for trail running?Katadyn BeFree 0.6LSalomon Soft Flask XA Filter 490ml/16oz 42Sawyer Mini Water Filtration SystemSteriPen Ultralight UV Water PurifierHow safe are water filters for trail running?SteriPen Ultralight UV Water PurifierWhat is the most effective water filter for trail running?Salomon Soft Flask XA Filter 490ml/16oz 42SteriPen Ultralight UV Water PurifierHow much water should I carry on a trail run?Aquatabs 8.5mg Tablets X30How do you know when it’s time to replace a water filter?Katadyn BeFree 0.6LDoes altitude affect water filter flow rates? Aquatabs 8.5mg Tablets X30Can my water filter be frozen?Aquatabs 8.5mg Tablets X30Can my water filter withstand being dropped?SteriPen Ultralight UV Water PurifierHow durable are the water filter flasks?Katadyn BeFree 0.6LAlli HartziRunFarSwitchback TravelTravel Oregon