The Best Emergency Water Purifiers: Top 11 Options Reviewed

I spend a lot of time in nature, so a reliable water filter is a must when I'm exploring the great outdoors. Just recently, my hiking group and I went on an overnight backpacking trip and I thought it would be the perfect opportunity to test out different water filters. Each of the filters we used was unique and I definitely preferred some over others.

Before we get into the details of the equipment we tested, we must first understand the difference between water filtration and water purification. In its simplest terms, a water filter is designed to filter debris, dirt, and most bacteria and protozoa from contaminated water. A water purifier, on the other hand, is not only designed to remove bacteria and protozoa from contaminated water but is also designed to purify the water from viruses.

In this article, we will highlight 11 of the most popular water purification systems and filters in the market today as well as their pros, cons, ideal uses, and our top picks (in no particular order). 

The Lifestraw water filter is, as the name suggests, a water filter straw. This straw works much like any other straw-- dip the bottom end into the questionable water and drink from the clean end. The 0.2-micron filter will clean dirty water as it makes its way to your mouth.

Cost: Around $15 apiece
Weight: 2 ounces
Filter type: Straw
Output: It has a maximum output of 1,000 gallons of water
Designed to remove: 99.99% of protozoa (such as giardia and cryptosporidium) and bacteria (such as salmonella, E. coli, and cholera).

Pros:

• It's extremely lightweight
• It takes up very little room and can fit almost anywhere
• It has a high flow rate
• It can be used multiple times

Cons:

• The drinking water that it produces is for immediate consumption only
• It's prone to clogging
• Some people experience difficulty sucking out of the straw due to clogging issues
• Cannot be used with a hydration reservoir

Best uses: Great for a car kit, survival kit, first aid kit, camping near bodies of water, fishing, and emergencies. Straw filters are also convenient to keep in your purse, gym bag, or backpack in case you find yourself in a situation where drinkable water is not readily available.

Click here to view it on Amazon!

This is a water bottle filter. The water bottle is made of soft plastic that easily collapses when empty and expands when filled. The filter is located at the connecting top attachment of the bottle. You can squeeze the bottle to push the potable water through, or suck through the mouth of the filter and drink.

Cost: Around $45
Weight: 2.3 ounces
Filter type: Bottle
Output: 2 liters of water per minute. Maximum output of 1,000 liters.
Designed to remove: Protozoa and bacteria

Pros:

• It's lightweight and can fit in small and tight places
• It has a wide mouth opening
• Easy to use
• There is no best-use time frame after using it for the first time. The performance of the filter is only limited to the quality of the water and the number of liters filtered.

Cons:

• The bags are delicate. Many people have had the bottle seam rip near the upper ridge by the handle.
• The manufacturer does not sell replacement bags individually
• The bag doesn't include caps for convenient storage
• The bottle does not stand up on its own
• If the filter dries out, it can cause low flow rates
• The hollow fiber filter is susceptible to freezing and can be damaged when frozen
• The bottle and filter can be a little tricky to clean once it has been used
• The filter does not offer a backflush solution
• The filter does not remove any tastes from the water

Best uses: This is a good option for personal use or for providing water to a small group. It's great for outdoor activities including backpacking, hiking, and camping.

Click here to view it on Amazon!

This water bottle purifier is designed for harsh environments. It comes in two sizes (16 oz and 24 oz) and several colors.

Cost: Around $70 for the 16 oz bottle and $90 for the 24 oz bottle
Weight: 10.9 ounces for the 16oz bottle, slightly more for the 24 oz bottle
Filter type: Bottle
Output: 2 liters of water per minute. Each filter processes approximately 250 liters.
Designed to remove: Chemicals, heavy metals, protozoa (such as giardia and cryptosporidium), bacteria (such as salmonella, cholera, and E. Coli), and viruses (such as SARS, Hepatitis A, and Rotavirus), as well as bad odors and flavors found in contaminated water.

Pros:

• This bottle doesn't just filter water, but also purifies it, meaning that it removes many viruses, chemicals, and heavy metals that other bottle filters don't.
• It's simple to use and requires no setup time
• It's easy to clean after use
• Makes water taste great
• Conveniently fits in almost all backpack pockets and vehicle cup holders
• The bottle can be refrigerated but not frozen
• You can drink right from the bottle or pour the clean water into a glass

Cons:

• It's slightly heavier than other purification systems
• A bit bulky
• It does not have a flip-top to drink out of
• The bottle and purifier pieces may be difficult to separate because of the suction that occurs. Those with weak hands or arthritis may want to take this into consideration.
• The purifier cartridge needs to be replaced every 150 or so liters. The bottle, however, can be used indefinitely.

Best uses: This is one of the best portable water filters for outdoor adventures, international travel, and emergency scenarios like natural disasters and survival situations.

Click here to view it on Amazon!

The Sawyer Squeeze is a simple and effective filter that connects to an attachable BPA-free bag. Drink straight out of the filter, squeeze the water into a new container, or let gravity do it for you.

The Sawyer Mini Filter is similar to the Sawyer Squeeze, except it doesn’t perform nearly as well as the Squeeze. The flow rate is much lower (about 30% less), so it might be worth your money to invest in the Squeeze Filter.

Cost: Around $35
Weight: 3 ounces
Filter type: Squeeze and gravity
Output: 1.7 ounces per minute. It can filter up to 100,000 gallons of water.
Designed to remove: Protozoa, bacteria, microplastics, and sediment

Pros:

• Easy to use and instructions are clear
• Easy to clean
• The squeezable bag comes with a cap so the water can be collected and filtered at any time
• The Squeeze filter will tread onto most standard water bottles
• If properly cared for, the filter can last a lifetime
• Gravity filters provide a hands-free experience so you can let your water filter while preparing a meal or setting up camp
• Squeeze filters allow you to push the water through the filter manually for the fastest flow rate

Cons:

• The squeezable bag it comes with is not the best quality. Many people complain that it breaks and develops leaks quickly.
• If it doesn't get backflushed, it will take a long time for the water to filter through.
• The filter is prone to clogging in certain water environments
• The filter will get ruined if frozen

Best uses: This is the most convenient and best portable water filter in my experience. It can be used for outdoor activities and for emergency preparedness in urban areas.

Click here to view it on Amazon!

The Vario Microfilter is designed to effectively clean dirty or polluted water. The water travels through a triple filter: a glass fiber filter, a ceramic pre-filter, and finally, an active charcoal filter.

Cost: Around $90
Weight: 15 ounces
Filter type: Pump
Output: About 2 liters per minute
Designed to remove: Waterborne bacteria, pesticides, some chemicals, and the bad taste in water.

Pros:

• Simple to use
• Has a high flow rate
• The ceramic filter is cleanable and reusable. If you keep the filter in good shape, it won't need to be replaced. The ceramic filters the cloudiness of the water and can be adjusted depending on the water source you're filtering from.
• Comes with a cleaning pad and carry bag

Cons:

• The carbon filter may remove some of the bad tastes in water, but possibly not eliminate them entirely. The carbon filter will need to be replaced every so often.
• A lot of people report issues with the o-rings failing, lack of lubrication, loss of suction, and leaking. If you experience any of these problems, we recommend contacting Katadyn directly for a replacement.

Best uses: This is a good choice for personal use, group use camping and hiking in the backcountry, and emergency preparedness.

Click here to view it on Amazon!

The Katadyn Hiker Microfilter is a convenient pump filter for backpacking trips and camping. It’s very low maintenance because it doesn’t require constant backflushing.

Cost: Around $75
Weight: 11 ounces
Filter type: Pump
Output: 1 liter per minute (if averaging 48 hand pumps per minute)
Designed to remove: Bacteria and protozoa

Pros:

• Ease of use
• Fast flow rate
• Great filter for large groups where large amounts of water need to be filtered quickly
• Pump filters don't require much strength or muscle power to work
• Ability to pump water into any hydration bladder, and a variety of containers or water bottles. This filter can attach directly to a 32 oz Nalgene water bottle.
• The pump has a long shelf life

Cons:

• This entire filter system is made up of several small parts. Even though it comes conveniently packaged in a zipper bag, it's bulky and will take up more room in your pack than other filters.
• The pump grip handle is poorly designed and a stable surface is needed in order to effectively apply downward pressure to the pump
• The filter can clog easily. It's recommended to pre-filter murky or dirty water (try wrapping a paper coffee filter around the inlet hose to filter out really large chunks of debris) and only use clear water for the pump. The filter needs to be clear in order for it to work effectively.
• There's no backflow cleanup for the filter
• The bottle adapter it comes with is a loose fit and it may be easier to put the output hose directly into the clean bottle
• The carbon cartridge needs to be replaced six months after the first use, or one year if the package is opened but not used. The replacement filter is a bit pricey.
  

Best uses: This is a great choice for camping, trekking, wilderness adventures, and as a backup solution for clean water during an emergency or survival situation.

Click here to view it on Amazon!

The Katadyn Pocket Filter is highly ranked among outdoor enthusiasts. It conveniently and quickly pumps crystal clear, drinkable water.

Cost: Around $370
Weight: 19 ounces
Filter type: Pump with a ceramic micro-strainer
Output: 0.86 liters per minute (approximately 70 pump strokes per liter)
Designed to remove: Protozoa, bacteria, and sediment

Pros:

• Very easy to use
• The pump handle grip is comfortable
• Water flows relatively fast
• Easy to clean and can be cleaned often for long-term maintenance (as well as on the field)
• Robust and durable. It is designed for a lifetime of use and comes with a lifetime warranty
• It has a silver-impregnated ceramic filter that inhibits bacterial growth inside its pores and provides up to 50,000 liters of treated water
• Every part of this filter is replaceable and can be entirely disassembled, if necessary

Cons:

• It weighs a lot. It's one of the heaviest filters on this list, and probably as heavy as it gets when it comes to portable filters.
• It's expensive but the good news is that it will last forever, so the long-term value makes up for the initial cost.
• Only filters down to a pore size of 0.2 microns
• The filter needs to be kept lubricated or else it becomes difficult to pump and gets squeaky
• Does not come with a carbon cartridge so the flavor of the contaminated water does not change once filtered
• Does not remove or neutralize chemicals in the water
• The inline filter elements will get ruined if exposed to freezing temperatures and conditions

Best uses: Long-lasting continuous use, backpacking, camping, hiking, emergency scenarios, and other extreme circumstances.

Click here to view it on Amazon!

The Survivor Filter Pro has a dual hollow fiber membrane and carbon filter that makes it much more efficient than many of the other water treatment devices on the market.

Cost: Around $70. Add another $30 if purchasing with additional carbon filters
Weight: 12.8 ounces
Filter type: Pump
Output: 17 ounces per minute
Designed to remove: Protozoa, bacteria, staph, and viruses. It also reduces heavy metals and improves the taste of water.

Pros:

• It's reliable, durable, and effective
• Easy to use
• It provides a good flow, especially when the pre-filter is clean
• Pumping the water is faster than gravity or squeeze filters
• It has a 0.1-micron pre-filter which helps to remove many waterborne pathogens. The ultrafilter has a pore size of 0.01 microns. This is one of the best filtration levels on the market.
• The pre-filter can be back washed and reused
• The pre and ultrafilters can process up to 100,000 liters of water. The carbon filter processes up to 2,000 liters.
• The cost of replacement filters is fairly low
• Leaves no discernible taste in water
  

Cons:

• It's somewhat bulky for hiking and backpacking
• It's heavier than other portable filter options
• Comes with a lot of attachment pieces and components (inlet and outlet hoses, hose clip, filters, etc)
• Hoses are flimsy so the pumping process becomes a little more difficult
• The carbon filter needs to be replaced every 500 liters. It's recommended that you buy this filter with extra carbon filters.
  

Best uses: Camping, emergency preparedness, and survival. It's a good idea to have the Survivor Filter Pro during times when you need to filter water from rivers, streams, lakes, and other questionable water sources.

Click here to view it on Amazon!

The MSR Guardian Purifier is a military-grade water purifier that is made in the USA. It is ranked the best portable water purifier by many and is made for harsh environments and heavy use.

Cost: Around $350, plus $190 for replacement cartridges
Weight: 17.3 ounces
Filter type: Pump
Output: 2.5 liters per minute
Designed to remove: Protozoa, bacteria, and viruses.

Pros:

• This purifier self-flushes during every pump stroke. In other words, the contaminants in the water get flushed back to the original source during every pump.
• It works great in shallow and deep water
• Water comes out perfectly clear and tastes good
• Can fill a variety of bottles and containers
• Designed to withstand freezing temperatures
• Can be put in long-term storage
• Can withstand drops of up to 6 feet
• Is capable of filtering up to 10,000 liters of water. The manufacturer provides information about proper maintenance and best practices to keep your purifier in tip-top shape.

Cons:

• A little heavier than other purifiers
• The filter needs to stay wet. If the cartridge is left inside its housing, the hollow fibers will stay properly moist and requires no action on your part.
• There's no indicator to let you know when the cartridge needs to be replaced
• Does not filter chemicals like chlorine or fluoride
• The hollow fiber element does not remove bad tastes and smells from the water
• Some users have experienced leaking but MSR claims the issue is linked to over-tightening

Best uses: Global travel, camping in the backcountry, emergencies, and survival.

Click here to view it on Amazon!

The SteriPEN relies on UV light to destroy harmful bacteria and purify water. It’s popular among outdoor enthusiasts and international travelers.

Cost: Around $120
Weight: 4.94 ounces
Filter type: UV light
Output: 32 fluid ounces per 90 seconds
Designed to remove: Bacteria, protozoa, and viruses.

Pros:

• Lightweight and small
• Easy to use
• Efficient
• It has a long battery life and can be recharged with any micro-USB adapter
• The battery holds its life during long periods when it's not being used, however, the manufacturer recommends recharging the SteriPEN every 6 months to maintain its performance
• Will treat approximately 50 liters of water during a single charge
• The UV lamp will last for 8,000 treatments
• Safely sterilizes clear water
• The LED indicator lights will let you know if the treatment was successful
• No need to worry about freezing temperatures, however, expect a shorter battery life when temperatures drop below freezing
  

Cons:

• It's dependent on its battery life and requires a USB charge
• The rechargeable battery is not designed to be replaced
• The instructions on the manual are vague
• Will only treat water that is clear and free of debris
• Does not work well with bottles that have a narrow opening (preferably 20mm or larger opening)
• Many people experienced a malfunctioning device after the first few uses
• The device does not purify water on the surface of a drinking container, such as the mouth of the bottle
• The manufacturer does not recommend treating more than 32 fluid ounces of water at a time with the SteriPEN

Best uses: This is the best choice for backpacking and traveling, so long that you have a way to charge it.

Click here to view it on Amazon!

The Berkey Filter doesn’t require electricity or plumbing to put together. It uses a variety of filters to produce some of the best-tasting water while retaining important minerals. The spigot makes it convenient for serving.

Cost: Around $400
Weight: 7 lbs for the container, plus additional weight for the filtration elements
Filter type: Stacked filter and water purification system with a height of 21 inches and diameter of 8.5 inches.
Capacity: 8.5 liters
Designed to remove: It removes pathogenic bacteria, viruses, cysts, and parasites entirely and extracts harmful chemicals such as herbicides, pesticides, VOCs, organic solvents, radon 222, and trihalomethane. It also reduces nitrates and heavy metals such as lead and mercury. It can remove food coloring in the water while retaining beneficial minerals in the water.

Pros:

• High-performance water filter and purifier
• Easy to set up and install. The instructions are straight to the point
• It's made of stainless steel. It's easy to clean and looks elegant.
• Filters water quickly
• Leaves the water tasting delicious
• The filter is good for up to 6,000 gallons of water
• Comes with different purification elements, depending on what your water needs to be purified from
  

Cons:

• Some people had difficulty priming the purification elements at first and setting it up can be confusing
• Bulky and takes up quite a bit of room in the kitchen
• Must be used consistently or bacteria can grow in the filters

Best uses: This is hands down the best emergency water filter for the home or office. It’s also ideal for off-grid living, emergency preparedness, and long-term camping. It's large and bulky, so it's not practical for travel and definitely not portable.

Click here to view it on Amazon!

Based on the reviews from my peers and my personal experience, the Sawyer Squeeze Water Filter System is the best water filtration system, in terms of being an exceptionally compact filter and being reliable in providing safe water for day-to-day needs as well as during an emergency situation. I've used my Sawyer Squeeze while traveling in North America and overseas and it has never let me down.

In any case, finding the best water filter or purification system ultimately depends on your needs and preferences. We hope the list provided above helps you determine what may be the ideal option for you.