Looking for the best camping filter? Clean drinking water is essential. To help in the backcountry, we researched over 30 backpacking water filters and tested the top 15 side-by-side over several months. So you don’t have to trust the companies marketing claims, we hiked into the wilderness and filtered over 100 gallons of water with these products.
We took multiple factors into account, such as how reliably a filter actually performs its purpose and how easy they are to use. This review highlights the comparative differences between the field of products to identify the best system overall, as well as the most valuable and ultralight options. We also break down the types of filtration systems to help you understand and select the most suitable model for your needs.
Best Overall Water Filter: Platypus GravityWorks
- Fastest treatment time
- Easy to use
- Requires little maintenance
- Can treat and store up to 8L
- No separate storage for clean and dirty hoses
- Hard to collect water from some sources
The Platypus GravityWorks encompasses our most favorite backpacking characteristics — lightweight, fast, easy to use, and versatile. This product took us by surprise, and it was definitely pleasant. We’re not all backcountry plumbers, and we were stoked that this model proved durable (with no breakable moving parts) and needed almost no maintenance.
The ability to treat small or large amounts of water quickly, as well as store and transport it, is clearly advantageous. It doesn’t treat for viruses, and so be sure to check the water quality of your planned destinations, especially outside of the U.S. and Canada.
This filter was closely followed in scoring by the MSR AutoFlow Gravity Filter, which has the same filter unit and a more durable bag, but no extra capacity. The new Katadyn Gravity Camp is hot on their heels as a contender for the best.
Best Value: Sawyer Mini
When it comes to performance-to-price ratio, our Best Buy pick gets it done. The Sawyer Mini only costs $25, lasts for 100,000 gallons, and is one of the lightest and smallest treatment methods reviewed. At 1.4 ounces for the filter, or a total of 2.4 ounces if you carry the straw attachment and a 16 oz soft bottle, this filter is light.
Versatile for several different uses, we like the Mini over the LifeStraw, which can only be used as a straw. The Mini can be used as a straw to drink from a source, it can be screwed onto a small-mouthed bottle to drink from, or it can be attached inline to a hydration bladder hose. At this price and weight, there is no reason not to protect yourself from possible water contaminants while in the backcountry.
Best Ultralight Filter: Aquamira Water Treatment Drops
If you are on a small budget, and the initial price of a filtration system is setting you back, the cheapest method is chlorine dioxide treatment, such as the Aquamira Water Treatment Drops. Fifteen dollars covers two single ounce bottles of drops, which treat 30 gallons. This is an effective and lightweight system that earns our Top Pick for Ultralight users.
This system is small, light, and can treat a large or small amount of water. It eliminates viruses and also kills Cryptosporidium if you wait one hour, which iodine, the other leading chemical treatment, does not. Aquamira is the top choice among ultralight backpackers and long distance hikers, but also a great choice if you’re heading out for a leisurely backpack. The only downside is that this treatment does not filter out particulate, so it is best used in locations with relatively clear water.
Best for International Travel: MSR Guardian Purifier
This purifying pump is our best pick for international travel because it is easy to use, maintains itself, and, best of all, filters viruses. We were amazed by the smooth handle operation and were able to fill a liter bottle in 47 seconds.
This unit back flushes with each stroke so it is always maintaining the same level of performance. This is a great choice for an urban, rural, or wilderness international traveler. It is painless to pull out the Guardian to give your drinking water some extra security.
We would not recommend taking the Guardian on backcountry trips in Canada and the U.S., since viruses are not much of a concern there. It weighs in at 22 ounces and has a steep price tag of $350. This is a worthy investment to protect yourself from pathogens that are more commonly found abroad.
Table of contents
Choosing The Best Filter for Your Needs
When evaluating various systems, the most important factors we considered were reliability and effectiveness, because if your system doesn’t work, then there is no point. Different systems treat for different hazards, and it is helpful to know what your system treats.
We think that three of the criteria evaluated are equally important: weight, treatment capacity, and ease-of-use. Weight is important because it is desirable to have a compact, lightweight system in the backcountry. A heavy, clunky filter weighs you down (and you are likely not to bring it with you).
We evaluated how well each system treats large quantities of water, so groups or hikers needing a lot of water at base camp can select an appropriate method. Ease-of-use is becoming a more prevalent selection criterion these days, and we agree that it is important. Filters no longer need to be cumbersome and there are some easy-to-operate filters in this review.
We compared how long it takes the system to filter (speed), and this was where we noticed a large difference between methods. Read on for more details and comparisons as well as other considerations, and check out the following table to see where each water filtering system ranked in Overall Performance.
Our latest picks are models that stood out from the pack for overall performance, value, or specific applications. For clarity in our test metrics, we inserted charts and tables which highlight the performance differences between each contender.
Reliability and effectiveness are related, but are slightly different; there are a few different sub-headings that fall under this category.
Effectiveness: This measures what the treatment system actually eliminates.
Systems That Treat Viruses
If you plan to travel internationally where water sources have a much higher likelihood of virus contamination, a system that treats viruses is strongly recommended. Here is a quick look at six systems that do treat viruses:
- UV light systems, like the SteriPEN Ultra
- Iodine treatments
- Chlorine Dioxide (tablets or drops) like Aquamira
- MSR Guardian Filter
- New gravity filters are now treating viruses too, like the Sawyer Complete 4-liter.
All other backpacking water filters remove bacteria, cysts, and protozoa, like Cryptosporidium (which some chemical treatments do not eliminate); they also remove particulate (which many of the above treatments do not remove).
Usually, protection against bacteria, protozoa, and cysts is all you need for hiking in U.S. and Canada. Virus protection is generally considered a need for international travel.
Chemical and UV treatments typically remove viruses, bacteria, and some protozoa but not the sediment from a, particularly dirty source. So, you won’t get sick from your water, but it might taste bad or look icky.
Different water treatment methods are effective on different types of organisms. The main difference in effectiveness in the systems reviewed is whether or not a system eliminates viruses or the hard-shelled (meaning hard to kill) protozoa Cryptosporidium.
Reliability is a measurement of how much you can rely on your system and if you are likely to need a backup system. We evaluated the durability of each unit based on its components, resistance to freezing, how much maintenance is required, and how difficult the required maintenance is.
Simple pump systems, like the Katadyn Hiker Pro and the MSR Sweetwater, are reliable. More complicated systems, like the UV light purifiers, are less reliable because of batteries or bulbs dying. We found our most reliable systems to be ones where not many things can break or go wrong.
The Platypus Gravityworks, Aquamira Water Treatment Drops, Sawyer Mini, and MSR Guardian all fill this requirement. The least reliable were the SteriPEN models, due to reports of malfunctioning, and the somewhat short battery life, which make us hesitant to bring them on multi-day trips.
The MSR Miniworks EX, MSR Guardian, and Sawyer Mini last a while before needing a replacement filter – they treat 2,000 liters, 10,000, and 100,000 liters respectively. The Sawyer Complete, according to its specs, can last for a million gallons, which is a lifetime of water treatment.
The Katadyn, MSR, and Platypus gravity filters all last for 1,500 liters. All of these are long-lasting, reliable options. The filters with the shortest lives are the Katadyn Hiker Pro and the MSR Sweetwater, which treat 750 liters.
Systems that had reported durability issues were the SteriPEN and the Katadyn Vario. One pair of hikers said the SteriPEN was ruined after getting rained on (although the new Ultra is watertight), and others reported random glitches with the light unit. The Vario has been reported to leak from between the filter casing and the pump housing after heavy use, though we did not observe this problem with either model.
How easy to use is each filter?
We measured ease-of-use based on how intuitive each system is and how many steps each requires to set up and treat water. We also considered the frequency of maintenance and the complication of back-flushing.
Chemical systems require no maintenance, as you typically add to water and wait. It doesn’t get much simpler.
The Sawyer Mini is one of the easiest systems: fill up your bottle and drink through the filter. Similar to this are the straw filters, like the LifeStraw, which allow you to drink from a stream or creek, or to collect water into a bottle and drink it through the filter later.
The runner-up for ease-of-use is the Platypus GravityWorks. The process of filling up the dirty bag, attaching the hoses, and waiting for it to filter is painless. It has an easy, one-step backflush process that involves inverting the clean bag over the dirty bag with no complicated disassembly. Likewise, the MSR AutoFlow is an easy-to-use gravity filter.
The Miniworks, Katadyn Vario and the Sweetwater lost points for their complicated maintenance routines. The Miniworks’ maintenance is fairly intuitive – simply open up and scrape the ceramic filter – but this process can be a pain and seems to be required relatively frequent if you’re using the filter regularly and for multiple people.
The MSR Guardian has revolutionized pump filter maintenance by having none. Instead, the Guardian self-cleans with every stroke, expelling dirty back-flushed water out a separate hose — we think this is great and wish that every filter had this feature!
The SteriPEN Ultra is simple to use: you push a button and the screen smiles at you when it’s finished. The main concern with this purifier is that the batteries need to be charged frequently.
Thankfully, in the new models tested, there is a trend toward ease-of-use and little-to-no maintenance.
Depending on how frequently you are in the backcountry or how many people you treat water for, you will likely want to consider how much water can be treated by your water filter system. Different methods have different limitations.
Pump filters allow for a seemingly endless amount of water. You can pump as much or as little as you need. All filter units need to be replaced eventually, but for the short-term, these clean water for a single person or a group for multiple days. All you need are some bicep muscles and time to sit and filter into multiple vessels.
Chemical treatments are not as cost-effective for long-term or large-capacity use but are light and easy for personal use. You can spend $15 on drops or tablets, and that leaves you with a limited number of treatable liters; for instance, a package of the MSR AquaTabs treat 60 liters for $13. When the chemical runs out, you need to buy more.
UV purifiers can only treat one liter at a time. This works fine for one person’s immediate drinking needs, but for large groups or treating water at camp, the process becomes slow and annoying.
Straw filters have a similar limitation. They are excellent for personal use, but since they only filter water as you, they do not work for groups or camps. With the Sawyer Mini, one can filter water for others and into different vessels, but it requires you to fill the provided soft bottle and manually squeeze the water through the filter into different containers. We found this process cumbersome and prefer to use the Mini to drink from directly.
Gravity filters excel at treating water for groups of people. They usually include 2L to 6L bags, and can quickly treat this amount of water. It takes under five minutes for the Platypus GravityWorks to treat four liters. These backpacking water filters are ideal for basecamps since they also provide a way to store water and have it ready for cooking.
Imagine this common scenario: You are backpacking and come to a stream where you can refill water. Your next water source will not be for six miles, so you need to maximize this source. Ideally, you will drink a good amount of water and fill up your bottles and/or bladder reservoirs to carry with you until the next source. This is when the time it takes to treat water matters.
Aquamira drops, our lightest system, takes up to an hour to fully treat for everything, including Cryptosporidium. This chlorine dioxide system kills most pathogens in the first 15 minutes, but that still requires a wait time that cuts into hiking hours.
The most immediate systems are the straw filters, the Lifestraw, and the Sawyer Mini where you can drink through the filter. However, the water flow through some of these is slow and you can’t carry very much water with you unless you decide to dedicate a vessel to carry dirty water.
Most pumps can filter a liter in a little over a minute, which is preferable, and they can treat unlimited amounts of water, unlike the systems that are limited by a specific bottle or container. The Katadyn Vario was the fastest pump system followed by the Guardian.
The fastest systems surprised us: the Katadyn Gravity Camp 6L filtered one liter in 40 seconds, followed by the Platypus GravityWorks and the MSR AutoFlow, each filtering a liter a minute. At first, we thought a gravity system would require the most waiting, but in fact, they worked the quickest, taking 3:05 for an entire gallon through the GravityWorks. And better yet, you don’t have to sit there and pump it, so you can fill it up and let it work while you snack or set up camp.
We think that gravity filters are the bee’s knees and everyone should consider owning one for their filtration needs. Even though chemical treatments are simple, the pump and gravity backpacking water filters are the best for a hiker on the go.
Weight is a huge concern since you will be lugging your treatment system on long hikes. Hiking is more enjoyable with less weight on your back, so selecting a treatment system that does not weigh more than your sleeping bag is a plus. Rather than going by the manufacturers’ specs, we weighed each system, including all the accessories and carrying cases that would be brought with them into the backcountry, to give you an accurate idea of the weight added to your pack.
The lightest water filter systems are usually chemical treatments, which are compact and almost unnoticeable. Aquamira Water Treatment Drops weigh 3 oz with their carrying caps. If you only want to bring a couple of individually wrapped chemical tablets, the MSR AquaTabs only weighs 0.2 oz for the whole package.
The Sawyer Mini is also one of the lightest systems, rivaling chemical treatments with a 1.6 oz weight for just the filter, proving even lighter than two full bottles of Aquamira. Next comes the LifeStraw, at 2.7 oz and the Katadyn Gravity Camp 6L at 11.5 oz. The heaviest, bulkiest systems were by far the Katadyn Vario, at almost 20 ounces, and the Guardian, at 22 ounces.
Once you’ve used a filter it will unavoidably be heavier than when you started, since it is difficult to get all traces of water out of the filter. Unless you have all day to wait for the filter to dry out, consider doing your best to dry your filter overnight. If you’re in cold climates, it’s best to bring your filter into your tent so it doesn’t freeze; while you’re at it, take it apart so it can dry.
We did not specifically score the products in this review but still think this is something to note. Though the taste is not a huge factor to consider, there is a noticeable difference between certain treatment methods.
Chemical treatments all change water’s flavor slightly. Iodine is horrible tasting, but the taste-neutralizing tablets do a good job of counteracting it. Chlorine dioxide does not add an unpleasant flavor to water, but it has a small background, pool-like taste.
Many filters improve water’s taste by cleaning chemicals and heavy metals and neutralizing odors, like the Vario. The SteriPEN is the one system that doesn’t change the flavor at all, positively or negatively.
For comparison’s sake, we did the math for you for the most cost-effective methods:
- The Sawyer Mini, treating a claimed 100,000 gallons, ends up costing a measly 0.00025 cents per liter.
- The Sawyer Squeeze, treating an estimated million gallons, costs far less per liter than any other option, a mere 0.002 cents per liter.
- The Katadyn Pocket, though by far the most expensive at the outset costing $370, treats 13,000 gallons, which averages to 0.7 cents per liter.
- The MSR Miniworks treats 2,000 liters, so it only costs about 4 cents per liter pumped.
The Platypus GravityWorks, which has a filter life of 1,500 liters, averages out to a cost of 8 cents per liter.
- The MSR Sweetwater, treating 750 liters, costs around 12 cents per liter pumped.
The Aquamira Water Treatment Drops, which treat 30 gallons per package, end up costing around 13 cents per liter.
- Katadyn Micropur Purification tablets, though cheapest at the outset, costs about 43 cents per liter to purify.
Some water treatment systems offer a pre-filter option, such as the SteriPen Water Bottle Pre-Filter, which helps remove large particulates to make sure the light penetrates all the water. The MSR Sweetwater Prefilter filters out particulates before it reaches the filter to help keep it cleaner longer.
Water treatment has come a long way in the last decade, and there is no one backpacking water filter system that is best for every application. However, there are some fantastic and versatile options. We hope that we were able to aid you in selecting the best backpacking water filter for your needs.
History of Water Filter and Treatment Systems
A brief history of water treatment leads to a better understanding of the current methods for filtering and treating water.
In the early 1970s, the Clean Water Act (CWA) was passed in the US as a response to contaminated water sources and the need to protect fresh drinking water for human consumption. Water safety concerns sparked a new era of water filtration and purification on the municipal level. Coinciding with the implementation of the CWA, reports of backpackers becoming ill from streams and lakes initiated backcountry water treatment development for the public; it was around this same time that hikers learned of Giardia in trailside water sources.
Up until this point, backcountry travelers rarely, if ever, experienced illness from drinking water directly out of streams, lakes, or rivers; the “Sierra Cup” refers to dipping a cup straight into the water and then drinking it with no treatment. The need for backcountry water treatment resulted from unsanitary practices, such as people not washing their hands after going to the bathroom or from stock defecating near or in water sources. Over time, these practices have impacted the purity of backcountry water. Present day issues have grown to include soaps and food particles in streams, rivers, and lakes.
Backcountry water filtration was born from centuries of water treatment history. Boiling water for improved taste dates back to 2000 b.c.e. It is believed that this method of water treatment was solely for better taste; water impurities had not yet been related to human illness.
Centuries later, Hippocrates is recognized for relating water to health by means of the “four humors.” The four seasons balance with the body’s “four humors” for equilibrium in temperature; if you had a fever, a cold bath could balance your temperature. is also known for the Hippocratic Sleeve – the first filtration method recorded. Water was poured into a cloth bag, after boiling, to capture sediment or debris, purifying the water.
Sand filters were the first effective form of municipal water treatment through France and other regions of Europe. The goal was to provide safe drinking and bathing water to every household. From the mid-1700s to the mid-1800s, municipal water plants were developed with slow sand filters that physically blocked the passage of contaminants as water moved through.
In 1590, the discovery of microscopic glass offered a magnified look into water droplets. Hundreds of years later, the ability to look at water on a microscopic level determined the correlation between cholera and poor water quality. This correlation also confirmed that clear water does not equate to pure water.
Although sand water filters were mandated throughout London as a response to the cholera outbreaks, the use of chlorine to purify water gained greater attention on a global scale. Chlorine decreased deaths related to poor water quality and waterborne illness. Chlorinated drinking water was the most effective at assuring public health; it has been used in municipalities worldwide and has also had a brief presence in the backcountry.
Chlorine tablets, or halazone tablets, were used for water purification during World War II but were replaced by longer lasting Iodine. (Chlorine is considered a poison and is therefore not a recommended method for water treatment.) Potable Aqua Iodine Tablets were developed in the 1940s and, like many other portable treatment options, were first used by the U.S. Army.
In the 1960s and 1970s, environmental initiatives began passing clean water and clean air acts. Water treatment plants were mandated in the United States to assure clean drinking water. Backcountry water filtration evolved from this point forward as water purity and safety became a concern.
Backcountry travelers would boil or chemically treat water for many years before portable pumps and filters were utilized. In fact, boiling water is still an effective, although sometimes inefficient, way to purify water.
Portable water filtration is recent, with a presence in the backcountry for the past few decades. Companies like Katadyn and MSR have had the greatest influence in modern water filtration systems.
In the 1930s, Katadyn developed ceramic water filters and over the next four decades expanded their treatment technologies, such as UV, throughout municipal plants. It wasn’t until 1999 that Katadyn’s water treatment became publicly available. Prior to this, they manufactured water filtration systems for municipalities and military.
In the 1980s, military forces used Reverse Osmosis Water Purification Units, which created potable water from a wide range of sources. The elaborate system involved polymers, cartridge filters, and high-pressure pumps to initiate and complete reverse osmosis. The water would then be forced through a cotton filter to remove sediment or particles and lastly would be treated with chlorine to preserve for later consumption.
These initial systems were large but later became small enough for portability and hand operation; the hand pumping creates the pressure that the initial model created with a machine.
In 1991, MSR designed the WaterWorks filter for backcountry users by combining carbon and ceramic technologies; it fulfilled the need for portability and reliability in water filter performance. In the same year, MSR brought the Dromedary Beverage Bag to market, providing renowned water portability.
The WaterWorks filter utilized a four-filter design: the first filter was a pre-filter made of porous foam and was intended to trap sediment, the next filter was a stainless steel screen that captured silt and algae, the third filter was designed of a carbon core and could remove bacteria and chemicals, and the fourth filter was pharmaceutical grade for sterile water – a membrane that removed any remaining bacteria. It became the most effective water filtration system for backcountry use. It was easy to field repair, easy to pump water through, fast, and innovative; the filter could attach to water bottles and dromedary bags.
In 1994, a ceramic core was added to the original WaterWorks design. This core had small pores for better filtration, was easy to clean, and was better suited for higher output. The new design became further streamlined by removing the screen filter (the second filter, as mentioned above). For the first time, carbon and ceramic technologies were combined for efficiency and ease-of-use.
In 1996, the MiniWorks came to market as a compact version of the WaterWorks filter. Both the WaterWorks and MiniWorks were upgraded with a Marathon Ceramic element. The main difference between the two filters was the final membrane that added size and weight to the WaterWorks and made the MiniWorks more portable.
As of 1997, MSR has had an in house microbiology lab
for assuring water purity beyond the standards set by the EPA.
The MiniWorks is a reliable water filtration system that is still popular today. In 2003, it underwent a facelift with the AirSpring Accumulator technology for even faster pumping. An air pocket in the filter adds efficiency to the design that many backcountry travelers depend on.
Water filtration continues to evolve with weight, efficiency, and ease-of-use in mind. In 2008, MSR introduced the Platypus CleanStream Gravity Filter; there are no moving parts—just hang and gravity efficiently does all the work.