The reality is that most backcountry water in the U.S. should only be consumed after going through a water filter. And, if you’re serious about not getting sick, a water purifier is even better. This is especially true in underdeveloped countries whose cities or wildernesses contain questionable water sources.
But what is the best water filter and purifier?
Below we summarize the best water filters and water purifiers for backpacking, hiking, camping, and overseas travel. We’ve deemed these the best water filters and water purifiers after a great deal of in-depth research and product testing. Keep in mind there are many different kinds of backpackers — we’ve split them up into five distinct Backpacker Types, and highlight the best water filters and purifiers for each Type below. Our recommendations are also broken down into three price-based categories: Budget, Classic, and Premium.
Some water filters or water purifiers will overlap Backpacker Types, so if you see the same product twice, know that it works for multiple activities.
The Best Water Filters for Backpacking
That lake or stream may look pristine, but it’s probably not. Better safe than riddled with Giardia, is what we always say. The water filters we picked for wilderness backpacking have a few things in common.
Diverse
Yes, diversity can be a commonality. Every water filter we recommend hits a different price point, method of filtration, and group size. You’ll want to pick the one you’re most comfortable with, and the one that makes the most sense for your style of wilderness backpacking.
Accessories
The beauty of these water filters is not just the excellent filter in each unit, but the extras they come with. As a backpacker you want to be adaptable in the field and before each trip. These filters have bags, carrying cases, or cleaning abilities, allowing you to customize your filtration system before each trip.
Filters, Not Purifiers
These filters are top of the line. They filter all protozoa, bacteria, and sediment down to .2 microns. Note that they are not water purifiers. Backpackers in the U.S. rarely need a purifier because viruses are not common in backcountry water.
Our Recommended Backpacking Water Filters
Platypus GravityWorks 4 L
At a Glance
- Weight: 10.75 oz (with all pieces and carrying case)
- Treatment Type: Gravity
- Retail Price: $119.95
Pros
- Comes with everything you need for many people, but can be broken down to fewer parts. Customizable to your experience, and everything fits in the included case.
- Each bladder is 4 liters in size, perfect for large groups that need water.
- High flow rate and easy connections make the "filtering" a passive experience.
Cons
- The filter unit on the GravityWorks is rather small, so it gets clogged. Back-flushing isn't difficult, but does take effort.
- It's expensive. You can rig a gravity filter system with the much cheaper Sawyer MINI or Sawyer Squeeze. The flow rate won't be as good, but if you're looking to pinch pennies this filter is expensive.
Sawyer Squeeze Water Filter System
At a Glance
- Weight: 3 oz. (for the filter)
- Treatment Type: Squeeze, Gravity, Inline
- Retail Price: $39.95
Pros
- High flow rate for such a small, simple filter. More than a liter per minute!
- Lots of included accessories, letting you customize your filtration experience. Gravity, squeeze, and inline all work out of the box.
- Lifetime guarantee for the water filter. With proper care (no freezing or crushing) it will last a lifetime of filtering.
Cons
- If you don't like all the accessories, it may seem overkill. You can't buy the filter alone.
- Some people don't like the squeeze method. If that's you, this filter probably isn't right.
- If used in freezing conditions there's a chance the filter will not work anymore, and you won't know. Keep it warm. (This is true of all hollow fiber filters.)
The Best Ultralight Water Filters and Purifiers
Even if weight is your primary concern, you will need a water filter or purifier. That water still isn’t clean. The water filters we picked for ultralight backpacking have a few things in common.
Super Light
We take the ultralight call seriously. There are fully featured water filters and purifiers that stay under four ounces.
Filtration and Purification
While a purifier isn’t always necessary for U.S.-based backpacking, ultralight backpackers are known to take their philosophy into other aspects of life, like travel or day hikes in foreign places. The purifiers below are best for those who want a foolproof water treatment system, no matter where they are.
Our Recommended Ultralight Water Filters and Purifiers
SteriPEN Adventurer Opti
At a Glance
- Weight: 3.8 oz.
- Treatment Type: Ultraviolet Purification
- Retail Price: $89.95
Pros
- Purifies 32 ounces of water in 90 seconds. Quick and light for full safety.
- No hassle, no moving parts, just need to remember batteries.
- Fits in a backpack hip belt pocket.
Cons
- Doesn't filter any sediment. You don't really want to drink water that has mud and sticks in it, so you'll need to find a fresh source or filter with a t-shirt.
- Uses batteries. These can run out, and then you can't purify your water.
Sawyer MINI Water Filter
At a Glance
- Weight: 2 oz.
- Treatment Type: Squeeze
- Retail Price: $24.95
Pros
- The ultimate quick, lightweight, cheap water filter. Sawyer MINI is used by countless backpackers and hikers. Many have one as a "spare" in addition to another water filter.
- Attaches to standard water bottle threads (like SmartWater) for increased versatility.
- Can be put inline with a water bladder for hands-free water filtering.
Cons
- It's so tiny that it clogs fairly often, and backflushing takes some time.
- The flow rate is poor. Don't expect a gushing stream of water.
- The included bags have a tendency to rip after too much use.
The Best Water Filters for Car Camping
The truth is that most campgrounds in the U.S. have potable water. At least the ones you pay for. If you car camp off the beaten path, near a stream or lake, you’ll need a water filter. And we’ve got you covered. The water filters we picked for car camping have a few things in common.
Low Hassle
If you’re car camping, you’re probably about ready to relax. The fact that you have to find and filter your water means the filtering itself should be a breeze. Our water filters for car camping are all self explanatory after first use.
Versatile
As you’ll see, all of our water filters for car camping are also used for other Backpacker Types. Needing a water filter for car camping is not the norm, so we figured the best water filters for this activity would be those that work equally well for other Backpacker Types.
Our Recommended Car Camping Water Filters
Platypus GravityWorks 4 L
At a Glance
- Weight: 10.75 oz (with all pieces and carrying case)
- Treatment Type: Gravity
- Retail Price: $119.95
Pros
- Comes with everything you need for many people, but can be broken down to fewer parts. Customizable to your experience, and everything fits in the included case.
- Each bladder is 4 liters in size, perfect for large groups that need water.
- High flow rate and easy connections make the "filtering" a passive experience.
Cons
- The filter unit on the GravityWorks is rather small, so it gets clogged. Back-flushing isn't difficult, but does take effort.
- It's expensive. You can rig a gravity filter system with the much cheaper Sawyer MINI or Sawyer Squeeze. The flow rate won't be as good, but if you're looking to pinch pennies this filter is expensive.
Katadyn BeFree Water Bottle Filter
At a Glance
- Weight: 2.33 oz.
- Treatment Type: Squeeze
- Retail Price: $39.95
Pros
- Easy to stash, store, and take with you. It's just two pieces -- the filter and the water bottle -- which lets you drink easily on the go.
- Incredibly high flow rate. The water comes gushing out.
- Can get larger size bottles from Katadyn or Hydrapak that still use this filter.
Cons
- Only a 1000 liter filter life. Other filters last much longer than that.
- If you filter extremely cold water the outside of the bottle will be cold. This makes the bottle hard to hold.
- It's also awkward to hold in general. Usually need two hands to tilt the bottle correctly.
The Best Water Filters and Purifiers for Hiking
During a day hike you’re probably able to survive off a pre-filled water bottle or hydration bladder. But you may prefer to get water during your trek, and that’s where water filters and purifiers for day hiking are clutch. The water filters and purifiers we picked for day hiking have a few things in common.
Immediate Water
Day hikers are perpetually on the move. You don’t want a filter or purifier that takes a while to set up, and you certainly don’t want to wait around for clean water. All our picks filter water immediately, quickly, and without any moving parts.
Filtration and Purification
For hikers in the U.S., purification is not always necessary. But if you’re hiking in underdeveloped countries (as many of us outdoor folk do), purification is absolutely necessary. Our Day Hiker picks tie in closely to the Urban Hiker picks, but if you just want filtration for standard U.S. day hikes, our Budget Pick is the best option.
Versatile
You’ll see some of these picks work across different backpacker types. Try to find the backpacker types you most associate with, and see if there’s a filter or purifier we recommend consistently. This will make sure you get you clean water whenever you need it.
Our Recommended Day Hiking Water Filters and Purifiers
MSR Guardian Purifier
At a Glance
- Weight: 21.7 oz.
- Treatment Type: Pump Filter and Purifier
- Retail Price: $349.95
Pros
- High powered treatment system that filters and purifies by pumping. Unique and unrivaled in the market.
- All one unit with no real moving parts, yet can be totally broken apart for advanced field cleaning.
- Automatically backflushes whenever you filter water. Almost no clogs, ever.
Cons
- Crazy expensive. This is the last filter or purifier you would ever need, but it will cost you.
- Really heavy when compared to most filters. This is due to heavy duty plastic and a large filtering/purifying unit.
- Doesn't screw directly into all water bottles. For the price, it should come with an adaptor.
SteriPEN Adventurer Opti
At a Glance
- Weight: 3.8 oz.
- Treatment Type: Ultraviolet Purification
- Retail Price: $89.95
Pros
- Purifies 32 ounces of water in 90 seconds. Quick and light for full safety.
- No hassle, no moving parts, just need to remember batteries.
- Fits in a backpack hip belt pocket.
Cons
- Doesn't filter any sediment. You don't really want to drink water that has mud and sticks in it, so you'll need to find a fresh source or filter with a t-shirt.
- Uses batteries. These can run out, and then you can't purify your water.
Katadyn BeFree Water Bottle Filter
At a Glance
- Weight: 2.33 oz.
- Treatment Type: Squeeze
- Retail Price: $39.95
Pros
- Easy to stash, store, and take with you. It's just two pieces -- the filter and the water bottle -- which lets you drink easily on the go.
- Incredibly high flow rate. The water comes gushing out.
- Can get larger size bottles from Katadyn or Hydrapak that still use this filter.
Cons
- Only a 1000 liter filter life. Other filters last much longer than that.
- If you filter extremely cold water the outside of the bottle will be cold. This makes the bottle hard to hold.
- It's also awkward to hold in general. Usually need two hands to tilt the bottle correctly.
The Best Water Purifiers for Urban Hiking
Urban Hiking, in this context, means hiking in and around international cities. The water purifiers we picked for urban hiking have a few things in common.
All Purification
When hiking in international areas it’s best to use a water purifier, not a water filter. This makes sure you don’t pick up a water borne virus, which are common in undeveloped countries.
Reduces Waste
The main way travelers avoid sickness from water while abroad is by buying bottled water. This creates a ton of waste. Some of you may have seen the waste piled up near beaches or just off the highway. Bringing a water purifier allows you to drink to your heart’s content — from a tap or local river — without buying bottled water.
Versatile
All of these purifiers are excellent for all hiking and backpacking activities. They are overkill for water treatment in the U.S., but they are quite versatile if you want a single purifier for home and abroad.
Our Recommended Water Purifiers for Urban Hiking
MSR Guardian Purifier
At a Glance
- Weight: 21.7 oz.
- Treatment Type: Pump Filter and Purifier
- Retail Price: $349.95
Pros
- High powered treatment system that filters and purifies by pumping. Unique and unrivaled in the market.
- All one unit with no real moving parts, yet can be totally broken apart for advanced field cleaning.
- Automatically backflushes whenever you filter water. Almost no clogs, ever.
Cons
- Crazy expensive. This is the last filter or purifier you would ever need, but it will cost you.
- Really heavy when compared to most filters. This is due to heavy duty plastic and a large filtering/purifying unit.
- Doesn't screw directly into all water bottles. For the price, it should come with an adaptor.
SteriPEN Adventurer Opti
At a Glance
- Weight: 3.8 oz.
- Treatment Type: Ultraviolet Purification
- Retail Price: $89.95
Pros
- Purifies 32 ounces of water in 90 seconds. Quick and light for full safety.
- No hassle, no moving parts, just need to remember batteries.
- Fits in a backpack hip belt pocket.
Cons
- Doesn't filter any sediment. You don't really want to drink water that has mud and sticks in it, so you'll need to find a fresh source or filter with a t-shirt.
- Uses batteries. These can run out, and then you can't purify your water.
How to Buy a Water Filter or Water Purifier
When it comes to buying a water filter, water purifier, or any piece of outdoor gear, there is one key concept to remember: It has to work for you.
We have spent countless hours researching and testing water filters and water purifiers, and we absolutely stand by each of our picks. They’re what most people will want out of a water treatment system, broken down by the type of trip you’re on and your budget. That said, you may not be “most people”. When it comes to buying a water filter or water purifier there are specific things to look for to make sure you’re buying the best water filter (or purifier) for you, not simply the “best” one on the market.
Water Treatment System
The main thing to consider when looking at a water filter or purifier is the treatment system. We go into great detail about each system in our Water Filter Guide, but here’s a brief bullet list of the common systems on the market right now:
- Boiling Water
- Chemical Water Treatment (Iodine or Chlorine Dioxide)
- Pump Filters
- Squeeze Filters
- Gravity Filters
- Straw Filters
- Water Bottle Filters
- Ultraviolet Purification
Each of these has its merits, and they all work to either filter or purifier water. Before purchasing a water filter or purifier, we recommend getting familiar with these systems and selecting the one that suits your personality and outdoor scenario.
For instance, if you only backpack with lots of friends or family to areas with plenty of water, a gravity filter will best best for setting up at camp. If you thru-hike alone, a squeeze or UV system may be best. All these pros and cons are parsed in our Guide.
Filtration vs. Purification
If you take one thing away from all the differences between treatment systems, it should be the concept of filtration vs purification. Which do you need based on your scenario?
Purification is overkill for most U.S.-based outdoor adventure. Filtration is more common, and also helps to get sediment out of the water.
If you need to treat water during travel, or any water that might have viruses in it, a water purifier is necessary. Don’t end up with a virus because you used a filter when you should have used a purifier.
Should I Buy a Water Filter or Water Purifier Online?
This question comes up more for outdoor clothing items, but it’s still valid for this type of gear.
The answer: Yes.
Water filters and purifiers don’t need to fit your body, and they always work out of the box. You can check them out in stores if you want, but watching a YouTube video or reading water purifier and water filter reviews will be almost as good.
Finally, remember to keep an eye out for when the specific model of water filter or purifier you want goes on sale. Nearly every outdoor online retailer and individual manufacturer has yearly sales. It is common to find the exact water filter or purifier you want for 30% off — this doesn’t mean there’s something wrong with it. It usually means there’s a warehouse overstock, or a new rendition of the product is coming out and the retailer or manufacturer is getting rid of the old ones.
With patience and research you can buy all (or most) of your backpacking gear at a discounted price.
