You don’t need much to have a successful backpacking trip. Yes, you’ll need some gear (like a tent, a sleeping bag, and a pack). But most importantly, you’ll need a way to get clean, safe water while on the trail.
Before we explain in depth how each water filter works, here are a few things that will help you through this guide. There are many different methods of filtering (or treating) water. The most common methods are through a cartridge or tube, with either activated carbon, UV light, or chemicals.
Filters also come in different styles: straw-style, pump filters, gravity filters, and UV or tablet treatments. They all make water safe to drink but differ slightly in size, durability, and price.
We’ve spoken to thru-hikers, hunters, and mountaineers, and read hundreds of customer reviews to find out which water filters on the market are truly the best.
Our team collectively tested a plethora of diverse filters for the creation of this guide. Current author and Senior Editor, Chris Carter, has been squeezing water through countless tubes and dropping tablets in his Nalgene each season to bring you the streamlined selection of 18 filters you see today. From stagnant green pools in the African savanna to bubbling alpine brooks in the Cascade Mountains, Chris has filtered water of all consistency and color in the wild, and brings only the best filters on his excursions. Rest assured, we would trust every model in this guide to keep us safe and hydrated in the backcountry.
Editor’s Note: We refreshed this article on November 24, 2023, adding additional details about our testing practices, more information regarding the difference between purifiers and filters, and several more photos. We also made sure our product list is up-to-date with current models, technology, and designs.
The Best Backpacking Water Filters of 2023
- Best Overall Water Filter: Sawyer Squeeze
- Best Budget Water Filter: LifeStraw Personal
- Best Filter for Thru-Hiking: Katadyn BeFree 0.6L
- Best Water-Purifying Tablets: Katadyn Micropur
- Best Gravity Water Filter/Best for Groups: Katadyn BeFree Gravity 3L
- Best Water Filter Bottle: GRAYL GEOPRESS Bottle
- Weight 2.5 oz.
- Filter type Bottle/inline filter
- Filter life Lifetime warranty
- Flow Rate 1.7 L/min
- Easy to use
- Included pouches aren’t very durable
- We love this filter for daily adventures and as a backup filter method on longer trips
- It lasts for up to 4,000 L, which is plenty for almost any outdoor adventurer
- It doesn’t work for filtering water into a bladder or bottle for reserve (you have to drink as it filters)
- You’ll also have to remember to empty the fiber chamber to prevent clogging before storing it away
- Fast flow rate
- Easy to clean
- Clogs up faster than some models
- Doesn’t fit as many water bottles as the Sawyer Squeeze
- Weight 0.9 oz.
- Filter type Chemical purifier
- Filter life 1 liter per tab
- Flow Rate 1 L/30 min.
- Destroy bacteria, protozoa, and viruses
- Lightweight, budget-friendly, and easy to stash in a pack, pocket, or a first-aid kit
- 4-hour wait time. (Because of this, we recommend treating your water ahead of time or in larger batches.)
- Expire after 5 years
- Requires no backflushing
- High flow rate
- You’ll need a place to hang the filter (so if you’re traveling to beaches or deserts, this might not be the best option)
Best Water Filter Bottles
Water filters aren’t just great for backpacking and hiking, but can keep you feeling healthy and fresh while road-tripping or traveling abroad. A few of the options below are great for both!
Below are some of our top choices for travel water filters, whether your adventures take you overlanding, RVing, on day trips, or on international adventures.
- Convenient and great for travel
- Doesn’t just filter water, but purifies it as well
- More expensive option
- 2-stage filter improves taste
- Durable build
- Sleek design with lots of fun colors
- Straw doesn't extend all the way to the bottom of bottle
- Straw cover cap unscrews relatively easily
- Weight 12.6 oz.
- Filter type UVC purifier
- Filter life 60 filter cycles per charge
- Flow Rate 1 L/90 sec.
- Fits in car cupholders as well as pack pockets
- It’s not cheap
- Needs to be charged
- Our bottle has suffered a few dents and dings (still works great!)
- Weight 7.2 oz.
- Filter type Bottle/straw filter
- Filter life 75 gallons per cartridge
- Flow Rate N/A
- Filters extremely small particles
- Nalgene-like durability
- Bulky base doesn’t fit into cup holders or pack sleeves
- Replacement cartridges are expensive
- Easy to use
- Efficient system
- Some wish the reservoir was larger
- Doesn’t require replacement filters as often as other choices
- You’ll have to pump it, although the flow rate is good enough to make up for the lost time.
- Weight Straw: 2.3 oz.; Squeeze Filter: 3.2 oz.
- Filter type Straw: straw; Squeeze Filter: bottle/gravity filter
- Filter life Straw: 4,000 L ; Squeeze Filter: 2,000 L
- Flow Rate Straw: N/A ; Squeeze Filter: 3 L/min
- Lightweight design
- Durable and sleek looking
- On the heavy side
- Squeeze filter has a shorter filter life than some
- Bags are clearly labeled "dirty" and "clean," so there's no confusion
- Overall performance is great
- The filter won't work in freezing conditions
- It tends to clog with silty water
- Some reviewers wished the seals on the reservoir bags were better
- Works great for group travel in the backcountry
- Requires no backflushing
- Purifies the dirtiest of water
- Easy to clean
- Unique carbon/ceramic filter design
- Pretty expensive
- Lighter than some other gravity filters
- Pretty slow flow rate
- Carbon filter needs to be replaced quite frequently
- Super long filter life
- Fast flow rate
- Easy to use
- Long lifetime
- Have to keep it charged
Backpacking Water Filters Comparison Chart
|Water Filter||Price||Weight||Filter Type||Filter Life||Flow Rate|
|Sawyer Squeeze||$39||2.5 oz.||Bottle/inline filter||Lifetime warranty||1.7 L/min|
|LifeStraw Personal||$20||1.6 oz.||Straw filter||4,000 L||N/A|
|Katadyn BeFree 0.6L||$45||2.3 oz.||Bottle filter||1,000 L||2 L/min|
|Katadyn Micropur||$16||0.9 oz.||Chemical purifier||1 L per tab||1 L/30 min|
|Katadyn BeFree Gravity 3L||$75||6.8 oz.||Gravity filter||1,000 L||2 L/min|
|GRAYL GEOPRESS Bottle||$100||15.9 oz.||Bottle filter/purifier||65 gallons||5 L/min|
|LifeStraw Go Series Bottle||$45||9 oz.||Bottle/straw filter||4,000 L||N/A|
|CrazyCap Bottle||$125||12.6 oz.||UVC purifier||60 filter cycles per charge|
1 L/90 sec
|RapidPure Purifier+ Bottle||$55||7.2 oz.||Bottle/straw filter||75 gallons per cartridge||N/A|
|Platypus QuickDraw||$50||3.3 oz.||Bottle/inline filter||1,000 L||3 L/min|
|Katadyn Hiker Microfilter||$80||11 oz.||Pump filter||750 L||1 L/min|
|LifeStraw Straw Filter & Squeeze Filter||$25 & $44||Straw: 2.3 oz.; Squeeze Filter: 3.2 oz||Straw: straw; Squeeze Filter: bottle/gravity filter||Straw: 4,000 L ; Squeeze Filter: 2,000 L||Straw: N/A ; Squeeze Filter: 3 L/min|
|Platypus GravityWorks 4L||$135||11.5 oz.||Gravity filter||1,5000 L||1.75 L/min|
|MSR Guardian Gravity Purifier||$300||1lb., 3 oz.||Gravity filter||3,000+ L||1 L/2 min|
|MSR MiniWorks EX Water Filter||$120||16 oz.||Pump filter||2,000 L||1 L/min|
|LifeStraw Flex Gravity Filter||$55||6.9 oz.||Gravity filter||2,000 L||0.5 L/min|
|MSR Guardian||$390||17.3 oz.||Pump filter/purifier||10,000 L||2.5 L/min|
|SteriPEN||$120||3.6 oz.||UV purifier||8,000 L||1 L/90 sec|
How We Tested Backpacking Water Filters
The GearJunkie team is made up of adventurers from a plethora of different outdoor sports and activities, but each of their hobbies requires a central discipline: proper water filtration in the backcountry. It’s key to survival, and if done poorly, can quickly put you in a dangerous situation.
Managing editor Mary Murphy curated our initial selection of 14 filters back in May 2020. A prolific backpacker, Mary knows the value of a reliable filter for constant, dependable hydration in the backcountry. Author and Senior Editor Chris Carter took over this guide in August 2022, and has been digging through his gear closet and scouring the internet ever since to bring you the most current, deserving selection possible.
Chris has thru-hiked the Triple Crown of long trails, (the Appalachian Trail, Pacific Crest Trail, and Continental Divide Trail) and continues to pursue long-distance hiking around the world. Significant time backpacking and hitchhiking around East Africa forced him to purify water of the grimiest sorts, and made him religiously fastidious in his hydration practices. He’s suffered from his fair share of water-born pathogens, and will only rely on the best of the best to filter his fluids on any adventure.
For this guide, we carefully scrutinized the most reliable, functional water filters that outdoor enthusiasts from all ends of the spectrum depend on in the wild. We brought each of these filters on adventures and made sure that we would feel comfortable with all of them as our primary means of accruing filtered water in the field.
Buyer’s Guide: How to Choose a Water Filter
Filters vs. Purifiers
Water filters and water purifiers work in similar ways, but it’s helpful to know the difference when choosing. Filters protect against protozoa or parasites (such as cryptosporidium and giardia) as well as bacteria (like E. coli or salmonella), microplastics, dirt, and debris. Bacteria is the main concern when you’re drinking out of unsafe water sources in the backcountry or remote areas. Popular filters include the Sawyer Squeeze and the Katadyn BeFree Gravity filter.
Purifiers go an extra step by protecting against and filtering out viruses. This is more of a concern when you’re traveling internationally or to rural places where clean water may not be accessible. Products like the MSR Guardian and GRAYL GEOPRESS Bottle will purify your water while also filtering out larger debris, while purifiers like the SteriPEN Adventurer use UV light to purify water, but won’t clear the water of visible dirt and sediment. You can run the water through a bandana or t-shirt first before using these types of purifiers to clean out the biggest particles.
For truly heinous dirty/stagnant water, it can be wise to use a number of different methods to make certain you don’t get sick. Some will filter their water with something like the Platypus QuickDraw, and then boil it, add a purification tablet like Katadyn’s Micropur M1 tablets, or add a couple of drops of bleach to ensure everything is killed. This can be time-consuming, and make the water taste interesting, but it’s far better than catching a trip-ending sickness in the wilderness.
Types of Water Filters
There are a variety of different types of backpacking water filters, and we cover a broad range of them in this guide. Each one has its place in the backcountry, and which type you choose will depend on how clear the water will be on your adventure, how lightweight you are trying to go, and if you are traveling internationally.
Gravity and Inline Filters
These filters use gravity to pull water from a dirty bag, through a filter, and into a clean bag or directly into your mouth. These are often the easiest filters to use as you simply hook it up to a tree branch or tent and wait. These are usually heavier and take some time to set up, so aren’t the best options for fast and light missions. They tend to work best for large groups or to keep around a base camp.
Gravity filters allow you to keep a large amount of water handy, but they can be difficult to fill up in shallow water sources, so keep that in mind when choosing a campsite. We found the Katadyn BeFree Gravity filter to be one of the best options for large group trips.
Inline filters are often used in gravity systems, but they can also be paired with a hydration pouch or water bottle for quick use. Filters such as the ubiquitous Sawyer Squeeze or the Platypus QuickDraw can be used in this way. These generally rely on the user sucking the water from a pouch or water bottle, through the filter, directly into their mouth. With the correct adapters, several models of inline filters can be used with a hydration pack you may already be carrying, offering easy filtration without adding much weight.
While we don’t recommend them as your primary method of water filtration in the wild, straw filters are undeniably one of the easiest ways of procuring fresh water fast. Our favorite budget filter, the LifeStraw Personal, fits this bill. These are great for trail running, mountain biking, or as a backup to your primary filter. These filters allow you to get down and dirty by a stream or lake and drink directly from the source by sipping the water through the filter like a straw.
The main downside to straw filters is that they don’t offer any way to carry filtered water with you, unless you can fit the straw into a water bottle of dirty water you are carrying with you, which can be really annoying. It can also get frustrating having to practically lie down on muddy or rocky banks to get a drink any time you get thirsty. These filters suffice for day hikes, but you’ll probably want something different for any extended backpacking trip.
Pump filters, such as the MSR MiniWorks, work great for pulling water out of shallow pools or creeks and can be a solid choice for small backpacking groups. They tend to run on the heavy side, take a little more effort to use, and can be quite complicated to clean. For these reasons, you don’t see as many pump filters in the backcountry as you used to, but they do still have their place.
In some cases, as with the MSR Guardian, pump filters do a better job at purifying truly nasty water, by removing viruses, bacteria, and protozoa, such as E. coli, giardia, and cryptosporidium. Something to consider a little more seriously while adventuring internationally.
Water Filter Bottles
Water filter bottles are handy to have for traveling, road-tripping, or light hiking, but are often on the heavy side for dedicated lightweight backpacking trips. Some of these bottles, like the LifeStraw Go Filter Bottle, filter water with a simple hollow-fiber straw that extends from the nozzle into the water, while others use fancier technology to deliver a pure, fresh swig.
The GRAYL GEOPRESS uses electroabsorption and activated carbon to purify water by simply pressing it firmly on the ground, while the CrazyCap bottle uses UVC light to remove viruses and bacteria. These aren’t your average Nalgenes! Check out our in-depth review of the GEOPRESS if you want to nerd out a little more.
Finally, purifying your water chemically, or with UV light, is another simple way to target viruses that may be present in a water source, as opposed to just bacteria and protozoa. Chemical purifiers use iodine or chlorine dioxide to deal with contaminated water, while UV purifiers employ ultraviolet rays. Some backpackers will also use bleach to treat their water (two drops per liter, then wait 30 minutes). This is a super simple solution but does leave your water tasting, well, somewhat like a pool.
We like Katadyn’s Micropur M1 tablets for chemical treatment, as they tend to leave a more subtle aftertaste compared to other brands. The SteriPEN Adventurer has been our go-to UV filter for its long lifespan and light weight.
This is a great way to purify your water more effectively, but since these don’t have filters with them, it’s important to use them with clear water that doesn’t have a lot of debris in it. Chemical or UV purifiers are lightweight and simple, but should probably not be used as your primary method of filtration on a backpacking trip. It’s hard to get filtered water fast, they can leave an unsavory aftertaste, and sometimes rely on batteries and electronics (in the case of UV purifiers). Since they are so light, however, it’s always a good idea to have them as a backup.
Filter Time and Flow Rate
Our picks for best water filters vary widely in terms of how quickly they can filter water, ranging from 30 seconds to 30 minutes to 4 hours (chemical treatments). Types of filters and methods of purifying will play a part, as will flow rate.
Flow rate is a unit that measures how quickly a certain amount of water can be filtered. Flow rates for gravity, pump, or squeeze filters listed here vary anywhere from 1L to 3L per minute. If you are encountering a slow flow rate with your filter, it may require priming or backflushing.
Similar to needing to prime a stove, some water filters require priming before initial use. Check the instructions (it varies by filter) on how to do this. Backflushing is a process where you need to clean water out of the filter system after use. This mainly applies to filters with pumps, tubes, or tubing, and it ensures that the inside of the filter stays dry and clean.
Another consideration here is location: if you are going to be traveling through a desert landscape, there may be few to no trees (a necessity to hang some gravity filters properly). For that type of setting, a different style of filter would be best.
And if you are going to be traveling with a companion or group, the personal LifeStraw filter obviously won’t be the best option (although we love it as a backup!).
This is an important point for ultralight setups and lightweight backpackers. You’ll want to choose a filter that works best for you and how much water you’ll need, but one that can also fit in your pack.
Filters like the Sawyer Squeeze and Katadyn BeFree are popular because the actual filter unit is so small, and the weight is close to nothing. The Sawyer Squeeze weighs just a couple of ounces, while the Katadyn weighs 6.8 ounces (but remember, it can filter up to 3 L of water at a time).
Filter systems that have water reservoirs and tubing also roll and pack down fairly small. Our personal preference on group trips is a gravity filter system, whereas on solo trips — though they weigh slightly more — our preference is a water bottle filter/purifier, given that we always carry a 1L bottle anyway.
Durability and Longevity
The lifespan of a filter greatly depends on its filter method (cartridge, hollow membrane, chemical, or UV light). Backpacking water filters can last anywhere from 250 to 4,000 L. Cleaning your filter regularly using the methods that the manufacturer recommends will also help prolong the life of your filter.
Filters that use a cartridge tend to last anywhere from 200 to 500 L before you need to replace the cartridge. On the other hand, with other filters that last longer, you may need to replace the entire unit at the end of its life. The LifeStraw is an example of this; it can filter around 4,000 L, and then it will stop working and need to be replaced.
The best way to clean your water when backpacking is to use and find the cleanest water source possible. You’ll want to look for clear, running water — somewhere between a babbling brook and a rushing river.
Avoid stagnant ponds or areas where there might be runoff (from livestock, urban areas, etc.) or debris. You’ll also want to find a safe place to refill, pump, or hang your gravity filter.
With some filtering methods, like chemical filters and tablets, you’ll want to wait longer to ensure that the water is clean if it’s below a certain temperature (or cloudy).
Filters most commonly use a tube, pump, or gravity method of filtering. Purifiers use a combination of a tube or chamber with activated carbon or another chemical component to fight against one key difference: viruses.
All of the choices on this list protect against at least bacteria and protozoa, and many also protect against things like toxins, chemicals, and viruses. We recommend choosing the one that will work best based on your situation, budget, and preference.
The lifespan of a filter largely depends on the type of filter. Most hollow fiber or activated charcoal cartridges will need to be replaced every couple hundred uses, or after a certain number of liters have been filtered. Some filters, like the LifeStraw, can last for years, but when it’s run its course you’ll need to buy a new one.
There are also some filters and purifiers that just need new batteries or to be charged.
Yes! Purifiers like the Grayl Geopress Purifier are built especially to filter and protect against everything you could encounter, whether in the backcountry or in a developing country.
As long as you are following the instructions on your filter or purifier, it will protect against whatever it’s rated for (usually something like 99.999999% of bacteria and 99.999% of parasites and microorganisms).
Our top two considerations when buying gear like this are always: (1) how often we will be using it, and (2) price. Another important factor for many is how long a filter will last. If you backpack or hike 9-12 months out of the year, you probably want to drop more money on a filter that has a longer lifespan.
When all else fails, you can boil water to be safe. But let’s be honest, having a water filter on hand is much better.