10 Best Backpacking Water Filters

We tested the best backpacking water filters on the market today according to price, weight, and ease of use. Read on to see how they performed, which is best for you, and get some valuable buying advice.

Best Backpacking Water Filters

The best backpacking water filters are:

• Best Overall Water Filter: SAWYER Squeeze
• Best Ultralight Water Filter: SAWYER Micro Squeeze
• Fastest and Easiest to Use Water Filter: KATADYN BeFree
• Best Budget Water Filter: HYDROBLU Versa Flow
• Best Chemical Water Purification: AQUAMIRA Water Treatment & Purification Drops
• Best Water Filter for Dirty and Silty Water: MSR Guardian Purifier

The product comparison table below is sortable. Click the arrow in the heading cell to sort the models by preferred spec.

Best Overall Water Filter

SAWYER Squeeze

Price: $40.95

See on REI See on AMAZON

Pros

✅ Best overall

✅ Good balance of features

✅ Lifetime guarantee

Cons

❌ Heavier

❌ Including bags known to fail

KEY SPECS

• Weight: 2.5 oz
• Life Span: Lifetime
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 1.7 L / min
• Type: Squeeze

The largest of the three Sawyer filters, the Squeeze is our top choice for the best water filter for backpacking, especially for thru-hikers who need a filter to go the distance. We like the Sawyer Squeeze for its filtration speed. It filters water at 1.7 liters per min, allowing you to fill a water bottle in less than a minute. We love that this fast filling allowed us to get back on the trail quickly.

Sawyer gives this product a lifetime guarantee and we’ve never had one fail. It does need frequent backflushing, which we find a little annoying at times, but if you are vigilant the flow rate will stay fast. The Squeeze includes pouches for collecting water, but the bags have narrow mouths and are difficult to fill, especially in streams or pools of water that are shallow. And we’ve had many of them fail after just a few squeezes. At 2.5 ounces, this is one of the heavier squeeze filters.

Best Chemical Water Purification

AQUAMIRA Water Treatment & Purification Drops

Price: $14.99

See on REI See on AMAZON

Pros

✅ Affordable

✅ Easy to use

✅ Lightweight

Cons

❌ Single use

❌ 30-minute wait time

KEY SPECS

• Weight: 1 oz
• Life Span: 30 gallons
• Prep Time: 30 min
• Protection: Bacteria, Protozoa, Viruses
• Flow rate: 0.45 L / min
• Type: Chemical

We found Aquamira to be the gold standard for chemical purification. It takes 30 minutes to destroy bacteria, protozoans, and viruses and hardly ever fails.

We found that chlorine dioxide adds a hint of a taste to your water, but it’s much less than other options we tested. It's relatively affordable, too, with a price tag of $15 for 30 gallons of treatment. However, if you’re filtering a lot of water the costs will add up quickly.

Aquamira quickly became a staple in our backpack because it is so easy to use. It ships in two bottles - the part A solution and the part B solution. You need to mix these solutions, wait until it turns yellow, and then add them to your water bottle.

The two vials together weigh a total of three ounces, but we found you can trim their weight by carrying just the amount you will need for your trip.

Best Ultralight Water Filter

SAWYER Micro Squeeze

Price: $32.95

See on MOOSEJAW See on REI

Pros

✅ Lightweight

✅ Long lifetime

✅ Fast flow rate

Cons

❌ Frequent backflushing needed

❌ Included bags known to fail

KEY SPECS

• Weight: 1.8 oz
• Life Span: Up to 100,000 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 1.4-1.9 L / min
• Type: Squeeze

The Sawyer Micro is our pick for the best ultralight hiking water filter. It is compact, lighter, and more affordable than the full-sized Sawyer Squeeze. It is almost as lightweight as the Sawyer MINI, but it has one significant advantage over the MINI - its flow rate. We loved the rapid flow rate and the compact size of the Micro.

It also is versatile as the other Sawyer filters. We used it with the included pouches, on a water bottle, and within a hydration system. The included bags are known to fail, so best to swap them out for something more durable.

Our biggest issue with this portable water filter is the frequent backflushing. Because it is so small it can get gunked up quickly, which will reduce the flow rate dramatically. We recommend backflushing after every use.

Best Budget Water Filter

HYDROBLU Versa Flow

Price: $22.95

See on HYDROBLU See on AMAZON

Pros

✅ Inexpensive

✅ Lightweight

✅ Long lifespan

Cons

❌ Requires frequent backflushing

KEY SPECS

• Weight: 2 oz
• Life Span: Up to 100,000 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 1-1.5 L / min
• Type: Squeeze

At first glance, the Hydroblu Versa Flow is a hiking water filter that looks like a dual-threaded Sawyer MINI, but the differences end there. When it comes to filtering speed, the Versa Flow outperforms the Sawyer MINI with a faster flow rate that lets you filter 1.25 liters in about a minute.

We like that both threads on the Versa Flow connect to standard 28mm water bottles and reservoirs. We were impressed that the dual threads add versatility to the filtration system allowing you to use the filter with a hydration bladder, in a gravity filtration system, or directly on a water bottle.

Keeping the filter clean ensures optimal performance, and we like that the Versa Flow makes that easy with an inspection window located on the side of the filter. The window allows you to see when the filter needs to be backwashed. It takes the guesswork out of cleaning and extends the lifetime of the filter. We like the price, at $23 it’s the cheapest squeeze filter on our list making it our best budget buy.

Fastest and Easiest to Use Water Filter

KATADYN BeFree

Price: $49.95

See on REI See on AMAZON

Pros

✅ Faster squeeze filter

✅ Easy to clean

✅ Lightweight

Cons

❌ Doesn’t work with standard bottle sizes

❌ Short lifespan

KEY SPECS

• Weight: 2.3 oz
• Life Span: Up to 264 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 2 L / min
• Type: Squeeze

The Katadyn BeFree is the fastest squeeze water filter on our list and the best water filter for backpacking if speed is your main concern. When filled, the BeFree filtered 0.6L liter in 25 seconds flat. It also was the easiest to clean - just shake it vigorously for about 30 seconds. We love that the entire unit (bag and filter) is ultralight, adding only 2.3 ounces to your base weight.

The BeFree uses a soft flask from Hydropack that has a wide 43mm mouth. We like that this wide mouth makes it easy to fill the container at water sources. However, one downside for us is that you’ll have to order a special water flask if it punctures.

We tested the 0.6L version and found it to be a tad small for hikes that don't have abundant water sources. We drank through the 0.6 liters very quickly and wished we had the 1.0-liter version. The biggest drawback for us is the lifespan. The BeFree only filters 264 gallons of water before it needs replacing. Not an issue for weekend trips but on a thru-hike, you may need more than one filter.

Best Water Filter for Dirty and Silty Water

MSR Guardian Purifier

Price: $389.95

See on MSR GEAR See on MOOSEJAW

Pros

✅ Fast filter rate

✅ Best option for dirty water

Cons

❌ Heavy

❌ Expensive

❌ Fussy to use

KEY SPECS

• Weight: 20.5 oz
• Life Span: 2600 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa, Viruses
• Flow rate: 2.5 L / min
• Type: Pump

When you are traveling to an area where there is contaminated water, then we recommend using the best filter money can buy, and that filter is the MSR Guardian. The Guardian is a powerhouse pump filter that can remove viruses, bacteria, protozoa, and even particulates from 2.5 liters of water in 60 seconds flat.

We don’t like that this is a little fussier than other options to use. The pump requires you to submerge a pre-filter into the water source and then use the pump handle to draw the water through the filter. We like that it backwashes the filter automatically with each stroke, keeping the maintenance down. And we like that if the filter gets clogged over time, you can easily replace it.

Our biggest gripe with the MSR Guardian is the filter outlet, which fits on a Nalgene bottle or similar-sized vessel. We also found that the filter leaked occasionally from the bottom and realized we had accidentally over-tightened the filter base. There is a small cutout that needs to be aligned to prevent the leak. The Guardian is the bulkiest filter on our list and weighs a whopping 20.5 ounces. It’s also the most expensive we tested costing you almost $400.

The Other Noteworthy Models

SAWYER MINI

Price: $24.95

See on REI See on AMAZON

Pros

✅ Lightweight

✅ Inexpensive

✅ Long filter life

Cons

❌ Slow filtration

❌ Frequent backflushing needed

KEY SPECS

• Weight: 1.45 oz
• Life Span: Up to 100,000 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 0.625 L / min
• Type: Squeeze

We like that the Sawyer MINI hits the sweet spot between affordability, with a price tag of $25, and lightweight, weighing a mere 2 ounces. Like Sawyer's other filters, the MINI is a reliable option to protect against dirty water. We did find that the small size meant we needed to frequently backflush this portable water filter. As long as we were careful to backwash, it never failed in our testing.

Our biggest gripe is its slower flow rate. After using the Sawyer Squeeze and Micro, it is hard to go back to the slower MINI. For occasional use or as a backup, the MINI is a great choice, but for thru-hikers who will be filtering a lot of water, we recommend the faster Sawyer Squeeze or Micro.

POTABLE AQUA Water Germicidal Tablets

Price: $15.99

See on AMAZON

Pros

✅ Lightweight

✅ Affordable

✅ Easy to use

Cons

❌ Wait time

❌ Single-use

KEY SPECS

• Weight: 2.24 oz
• Life Span: 8 gallons
• Prep Time: 4 hrs
• Protection: Bacteria, Protozoa, Viruses
• Flow rate: 1.8 L / min
• Type: Chemical

We like that the Potable Aqua is the absolute lightest form of water purification you can bring on the trail. A package that can treat up to 30 liters of water weighs a mere 0.21 ounces. Potable Aqua also is the easiest to use. You simply open the blister pack, drop in a tablet, and wait for the chlorine dioxide to do its magic.

The waiting period was the biggest drawback to the Potable Aqua. Each treatment takes thirty-five minutes, which is considerably longer than, say, a squeeze or pump filter. Just like Aquamira, Potable Aqua does not leave an aftertaste. We drank the treated water right from the bottle without having to add any flavoring.

Though we pre-filtered any turbid water, we found that Potable Aqua often removed some of the residual organics by causing them to fall out of suspension. We found that the water was more clear after the treatment cycle.

KATADYN Steripen Ultra UV

Price: $129.95

See on REI See on AMAZON

Pros

✅ Easy to use

✅ Protects against viruses

Cons

❌ Needs batteries

❌ Doesn’t filter silt and debris

❌ Expensive

KEY SPECS

• Weight: 2.7 oz
• Life Span: 8,000 uses
• Prep Time: 90 sec
• Protection: Bacteria, Protozoa, Viruses
• Flow rate: 0.63 L / min
• Type: UV

The Steripen Ultra was our favorite water purifier because of its convenience and effectiveness. You literally stick the probe into your water bottle, turn it on and stir. We love the LCD display that tracks the time and takes the guesswork out of the sterilization process.

Unlike filters, the Steripen protects against viruses as well as bacteria and protozoa. And we like that unlike chemical treatments, there is no funny aftertaste. It won’t filter out silt or debris so we recommend filtering water through a bandana if your source isn’t clean.

As easy and effective as the Steripen is, it has a few drawbacks. We found the probe will only fit into a wide-mouth bottle, so we were forced to ditch our Smartwater bottle and carry a heavier Nalgene. It also uses a rechargeable battery, and won't operate when it is low. You need to bring a charging cable and power source, which adds even more weight to your pack.

Then there is the cost. Because of its electronics, the Steripen is priced over $120 and is one of the more expensive options on our list.

MSR Trail Shot

Price: $62.95

See on MSR GEAR See on MOOSEJAW

Pros

✅ Durable

✅ Collects water from shallow sources

Cons

❌ Expensive

❌ Slower flow rate

KEY SPECS

• Weight: 5 oz
• Life Span: 528 gallons
• Prep Time: Instant
• Protection: Bacteria, Protozoa
• Flow rate: 1 L / min
• Type: Squeeze

The MSR TrailShot is a versatile filter that takes the best parts of a pump filter and packages them in squeeze-filter-style packaging. It's a durable system that can handle backcountry adventures without failing. Make sure your hands are in shape, we found squeezing the bulb of the filter can be tiring when you need to filter more than a liter at a time.

The winning feature of the TrailShot is its long hose that collects water from even the smallest puddles. In a pinch, we filtered water from rainwater that had accumulated in a depression on the solid rock face of a bald summit. No other filter, except the MS Guardian, could have harvested this water.

As an added benefit, the hose has a mesh that functions as a pre-filter to remove suspended solids from clogging the filter. The TrailShot also is easy to clean, simply shake it to clean the filter and restore the flow rate.

The output end of the TrailShot ends at a small spout. You can drink directly from the spout or point the spout so you can filter water into any sized container. It also can be connected in line with an MSR Trail Base kit to create a gravity filter.

Key Factors To Consider When Choosing

Price

Chemical options and squeeze filters are the least expensive, often under $50. 90% of the time these are the way to go. Premium models like a UV steripen, which include electronic parts or, in the case of the MSR Guardian, are designed to be rugged and last a long time. These options can be almost $400.

Backpacking water filters that provide the greatest value:

• SAWYER Squeeze
• HYDROBLU Versa Flow
• AQUAMIRA Water Treatment & Purification Drops

Affordable backpacking water filters:

• AQUAMIRA Water Treatment & Purification Drops
• POTABLE AQUA Water Germicidal Tablets
• HYDROBLU Versa Flow

Premium backpacking water filters (most expensive):

• MSR Guardian Purifier
• KATADYN Steripen Ultra UV
• MSR Trail Shot

Weight

Look for the lightest weight filter or chemical set that will safely filter water to suit your needs. Most squeeze filters weigh under 3 ounces and chemical options are even less. Pump filters weigh the most, often over a pound. We only recommend them when you need a heavy-duty option.

The lightest backpacking water filters:

• AQUAMIRA Water Treatment & Purification Drops
• SAWYER MINI
• SAWYER Micro Squeeze

Ease of Use

Ease of use boils down to several factors, many of which we’ll cover in more detail below. When judging how easy a filter is to use, look for a filter that has a fast flow rate and is compatible with your water bottle or comes with its own.

Also, you want a filter that requires minimal maintenance like backflushing. Chemical water treatments are the easiest, simply add a few drops or a tablet into your water bottle and wait.

The easiest-to-use backpacking water filters:

• AQUAMIRA Water Treatment & Purification Drops
• POTABLE AQUA Water Germicidal Tablets
• KATADYN BeFree

Other Things to Consider

Types of Filters

SQUEEZE FILTERS AND GRAVITY FILTERS: THE POPULAR CHOICE

With squeeze and gravity filters, you collect your water in a small pouch or water bottle and attach the filter by screwing it onto the end of the vessel. You then squeeze the bottle or pouch to push the water through the filter.

You can also hang it upside down and let gravity pull the water through the filter. It only takes a minute or two to fill your water bottle with fresh, clean water. Because they are lightweight and easy to use, filters are a popular choice among backpackers.

WATER PUMPS: THE HEAVY-DUTY SOLUTION

Water pump filters use a pump to force water through a small-pore filter membrane (0.02 microns or smaller). They have a tube that you place in your contaminated water source and a pump handle that you squeeze to filter the water into a clean water bottle. Most pump filters have replaceable filters that need to be cleaned regularly and changed when they are so gummed up that they can no longer be cleaned.

CHEMICAL: A GOOD BACKUP PLAN - SLOW, BUT COMPACT AND LIGHTWEIGHT

Chemical purification is the most common filtration method. It is popular because it is portable, easy to use, and less likely to fail. You only have to carry around a small vial of chemicals or a handful of small tablets. As long as the chemicals have not expired, they work effectively to destroy bacteria, protozoa, and viruses. You simply add the chemicals and wait for them to work.

The chemical reactions take time, so you must treat your water before you need to drink it. Depending on the type of chemicals you use, you may have to wait up to four hours before you can drink your water. Not everyone likes chemical purification as some of the chemicals used to sanitize your water can give it an off-taste.

It also takes longer to work as temperatures decline. Because of these drawbacks, many long-distance hikers carry a filter to treat their water and use chemicals as a backup in case their filter fails.

The Katadyn BeFree is water filter that doubles as a water container. Fill it up and drink up.

UV: THE SYSTEM THAT ALSO WORKS IN COLDER WEATHER

Another popular purification method is UV sterilization, which uses a wand with a UV light source to scramble the DNA of bacteria, protozoa, and viruses. You place the wand in your water source, turn it on and stir for a minute or two. It's quick and doesn't change the taste of your water.

Because it uses light, you need to carry batteries or a portable charger to keep it powered though. Unlike chemical purification, UV purification still works even when it is cold out. You do need to pre-filter the water to remove any particulates as it loses its effectiveness when the water is turbid.

BOILING: IF ALL ELSE FAILS - REQUIRES TIME AND FUEL

Boiling is another method that is effective at killing bacteria, protozoa, and viruses in water. It doesn't change the taste of the water and doesn't require battery power, but it does take time and fuel. You should bring your water to a rolling boil and boil it for at least one minute.

At altitudes higher than 6,562 feet (2000 meters), you should boil your water for 3 minutes Because of the cost and weight of carrying extra fuel, most hikers use boiling as a backup in case their primary method fails.

Common types of water filters.

Lifespan

Most filters have a maximum amount of water they can filter before replacing. You will often see this advertised as the number of gallons the filter can handle. The Sawyer MINI, for example, can filter up to 100,000 gallons before you need to replace it. Most filtration units are disposable. Once you reach their limit, you need to replace the entire unit. Some, like the MSR Guardian, ship with replaceable filters.

Prep Time

Not every purification method delivers potable water in an instant. Some filters require assembly or priming before they can produce clean water, while chemical processes require time to neutralize pathogens. Make sure you know how long your method takes and plan appropriately. We recommend carrying an instant filtration option as your primary filter, especially in hot weather when you’ll be filtering water more frequently.

Taste and Odors

Some filtration and purification methods can remove tastes and smells, but most do not. In fact, some chemical purification methods, like iodine, add an unpleasant taste to the water. If you don't like the taste of your water, you can always add a drink mix packet to cover it up. Note most natural stream and spring water tastes phenomenal though! It's oftentimes those stagnant and dirty water sources that can have a strange taste.

Chemical treatment takes time but remains a very lightweight and effective way to purify water.

Protection

Not all hiking water filters protect against the same contagions. Squeeze water filters often don’t protect against viruses. Pump filters have a smaller filter diameter which protects against more harmful bugs. Chemical treatments should kill everything in the water and are the best option when your water source is especially dubious. In extreme cases, we recommend filtering with a squeeze or a pump filter and then chemically treating your water.

Flow Rate

Flow rate measures the amount of water that can pass through a filter. The faster the flow rate, the faster you can filter your water. There is nothing worse than a slow flow rate filter that seems to take forever to filter. Our favorite water filters have a fast flow rate giving us more time to hike and less time waiting for water to filter.

Packability

Bring what you need for your trip, but don't overpack. Most filtration units and chemical treatments are pocketable and take up minimal space in your backpack and 90% of the time we recommend these options. If you are going into an area that has heavily contaminated water, then you may have to sacrifice some space to get a larger and more robust pump filter like the MSR Guardian.

With the MSR Guardian, you can pump clean water directly into your Nalgene.

Compatibility

Filtration units often ship with a bag or pouch that you use to gather water. The filter then screws onto the container, and you squeeze it to force the water through the filter. Some filtration units are designed to fit in line with a hydration bladder or attach to a refillable plastic water bottle. Make sure you purchase a filter that is compatible with your current hydration system.

Maintenance

Most filters require you to backwash them after each use. Backwashing removes any particles that stick to the pores of the filtration membrane. If you don't backwash regularly, you may clog your filter and significantly reduce its lifespan. You also need to protect your filter from freezing conditions as ice crystals will put holes in the filter membrane. When temperatures fall below freezing, you should carry your filtration unit near your body during the day and in your sleeping bag at night.

Durability

Most filters have a durable construction. However, there are issues to watch out for. With squeeze filters freezing often will ruin a filter. Take care when temperatures near freezing by sleeping with your filter in your sleeping bag. Make sure any liquid chemical filters are in bottles that won’t break, leak, or crack. With pump filters, be careful with the pump handle to avoid breaking.

Squeeze filters are instant. Simply fill up your water container at the source and squeeze clean water out.

What Pathogens to Watch Out For?

Water-borne pathogens can be broken down into three major categories - bacteria, protozoans, and viruses.

BACTERIA

Bacteria commonly found in water, especially in North America, include Escherichia coli (E. coli), Salmonella, Campylobacter, and Shigella. Common bacteria are not very serious. Symptoms usually include diarrhea, stomach cramps and sometimes vomiting as well as fever. Enough to get you off the trail for a week or two.

PROTOZOANS

Protozoans include Cryptosporidium and Giardia. Similarly to the bacteria mentioned above, these micro-organisms will cause stomach infections that will manifest in the form of diarrhea and stomach pains. The infection usually clears up within two weeks, sometimes more.

VIRUSES

Viruses found in contaminated water include hepatitis A, rotavirus, and norovirus. Water-borne viruses are rare in North America; they're more commonly found in areas with poor water sanitation and can lead to a wide range of infections that take several months to heal up.

Hepatitis A, for example, is a liver infection whose symptoms can last up to 6 months and include extreme tiredness, loss of appetite, dark urine, and yellowing of the skin and eyes. On the other hand, the effects of norovirus (commonly referred to as "food poisoning" or "stomach flu"), usually wear off within a few days.

The Steripen Ultra is a UV purification system that uses light to destroy pathogens.

Which Water Sources to Filter From?

You'll encounter a variety of water sources on the trail that range from murky swamps to fast-flowing streams. The best water sources are clear and fast flowing. Avoid stagnant water sources which tend to accumulate algae and other particulates. These floaties will clog your filter and taste nasty when you drink them.

If your only water source is turbid, then you should pre-filter the water through a bandana or a t-shirt to remove large particulates. If you don't have any clothing to spare, then you can use sphagnum moss or sand packed into a soda bottle. You also may want to have a cup or extra bottle handy to help scoop out the water from a shallow stream.

The MSR Trail Shot lets you squeeze water straight from the source into your container.