In an SHTF scenario, it’s critical to have the best emergency water filter to ensure your survival.

You can survive only three days without water and you know finding a reliable, clean source, in times of an emergency won’t really be the easiest thing to do. Prepare now and avoid the agony later.

I’ve put together a list of the 7 best survival water filters there are. Which one will best suit your needs.

In a Hurry? Here are Our Top Picks

What to Look for in an Emergency Water Filter

I’ve considered multiple factors while deciding on which water filter is best in case of an emergency. Something that works when you’re out camping, may not be the best choice when things hit the fan. That being said, here are some factors I’ve considered.

Portability and ease of use – In the event of an emergency, you don’t want a large, heavy filter weighing you down. I’ve looked at how easy they are to carry around, and how simple they are to use – can your kids use them on their own?

Filter rating and maintenance: – Emergency water filters use mesh screens to block out particles and how effective a filter is depends on how small the pores on the filter are. This is denoted in microns. For reference, human hair is 50 microns wide, while most bacteria range between 0.2-1 micron.

Maximizing the life of a filter will also require some sort of basic maintenance; and some units offer limited scope to do that, so that’s worth considering, as well.

Durability – Brands usually reveal how many gallons of water their product will be able to filter effectively before the filter starts to degrade.

Cost per gallon – As I just mentioned, a filter offers optimal performance only for a certain quantity of water. Cheap filters may seem like a tempting option at first glance, but you’ll find that a good quality one, despite being a more expensive initial investment, is often a better deal in the long run.

Best Personal Water Filters

Sawyer Squeeze Water Filtration System

The Sawyer Squeeze is one of the most popular filters amongst preppers because it packs a lot of value and versatility into a compact and affordable package. The popular, more affordable Sawyer Mini is a very impressive product as well, but I’ve found that it has some cons that the Squeeze addresses.

Portability and ease of use: The Sawyer Squeeze is a compact unit that’s shaped like a tiny water bottle. It weighs under 3 ounces and measures 6 inches long and 2 inches wide – small enough to easily slip into your bug out bag.

One of our favorite aspects of the Sawyer Squeeze is the versatility; it’s threaded at the bottom, so you can screw it to almost any water bottle and drink straight from it. Sawyer also offers durable accessory pouches, so you can fill them with dirty water and let the Squeeze filter water into a water bottle.

Be careful when you unscrew the Squeeze as it has an O-ring that does tend to come off. If this does happen, water does leak from the connection point.

Filter rating and maintenance: The filter on the Squeeze is rated at 0.1 microns – enough for bacteria, microplastics, protozoans, and sediments. You will need another system to filter viruses or chemicals.

The unit also comes with a syringe and coupler for cleaning the filter back to 98.5%. That said, I found that attaching a water bottle to the coupler and squeezing it back flushes with more water and higher pressure.

Durability: Sawyer has not revealed an exact lifespan for the Squeeze on its website, but the Sawyer Mini that uses the same filter offers a whopping 100,000 gallons! From some perspective, you can drink 1.5 gallons through this every day and it will last you 182 years.

Cost per gallon: At $0.0003, the cost per gallon is far lower than other filters on the market. For example, the popular LifeStraw (that’s next on this list) comes in at 1.5 cents per gallon.

Verdict: If you’re on a budget and had to choose just one personal water filter system, the Sawyer Squeeze is your best bet. The Sawyer Mini costs about $10 less, is smaller, and offers the same levels of filtration and versatility, but it takes nearly twice as long to filter water. Since it’s larger than the Mini, it also doesn’t have to be backflushed as often.

Pros:

• Versatility
• Accessories
• Flow rate

Cons:

• Seals/attachment points tend to break

LifeStraw Personal Water Filter

LifeStraw is a brand that’s become synonymous with the survival straw, over the last few years. However, they may not be the best choice.

Portability and ease of use: A LifeStraw personal water filter is 9 inches long and weighs less than 2 ounces (46 g, to be precise), so you can carry one with you anywhere. You could even have one in your pocket at all times. And since they work just like a straw, you could even teach your child to use one in a matter of seconds.

But, that’s also where one of its biggest flaws lie. Since it works like a straw, you have to get very close to the water source to use it – not something you want to be doing if the water is contaminated. It’s also not a very versatile product. No 28mm threading means you can’t screw it to your water bottle or hydration pack – it works only as a straw.

Subsequently, this also means that you can’t filter water to store it for later.

Filter rating and maintenance: The filter in LifeStraw is capable of removing bacteria and parasites. The company claims that it can filter out waterborne bacteria, including E. coli and salmonella, along with parasites like cryptosporidium and giardia.

It can’t, however, filter out minerals, viruses, or chemicals. It does a decent amount of filtration for the price, but there are units (like the Sawyer Squeeze above) that do a better job.

Another major downside is that you can’t backflush a LifeStraw (again, unlike the Sawyer Squeeze that comes with a backflushing syringe) and so, if your LifeStraw gets blocked, there isn’t much that you can do. You could try and combat this by blowing air through the straw after every use, but again, not a fool-proof technique.

Durability: The LifeStraw has no moving parts, so it’s not going to break easily. And it has no shelf life. So you can stack upon them and they’ll be ready to go when the time comes. The LifeStraw can filter up to 1,000 gallons of water – that’s a lot!

The average human consumes between 1-2 gallon per day, so it’ll be a while before you use one up.

Cost per gallon: They’re also pretty cheap. The average cost per gallon is under 1.5 cents, and you can reduce that number by buying them in bulk.

Verdict: The LifeStraw is hard to beat when it comes to value for money. It does have its flaws, but if you’re looking for a backup filter that you can have on you at all times, this is one to consider.

Pros:

• Affordability
• Portability
• Ease of use

Cons:

• Works only for individuals
• Can’t be backflushed or repaired
• Not very versatile.

LifeStraw Go Bottle

A filter-enabled water bottle is as convenient as water filters can be. They’re a good way to hit two birds with one stone as they also allow you to store water. Our choice is the LifeStraw Go.

Portability and ease of use: There’s little to say about the portability and ease of use of a water bottle. The LifeStraw Go is a quality 22 oz bottle that weighs 5.9 oz.

Just fill it with water and sip away.

Filter rating and maintenance: A 0.2 micron helps filter out bacteria, sediment, and protozoa, but is inefficient against viruses. If you want virus protection, the Sagar Journey is a good option. However, it has a large 2.0-micron filter – the company says it uses an active filter membrane that charges the mesh to attract and trap smaller elements.

Back to the LifeStraw Go; the filer is not back washable, so you’ll have to be careful about allowing build-up.

Durability: The 0.2-micron filter is good for about 100 liters (26.4 gallons), after which replaceable $10 carbon filters can be bought. The bottle itself is made of sturdy BPA-free plastic and will get by with a few scuffs even if you drop it.

Cost per gallon: Cost per gallon is the highest on the list at $1.32 for each gallon that it filters – the cost of convenience.

Verdict: There’s no replacing the convenience and ease of use that a filtered water bottle provides, but as you can see, it comes at a cost. We’d recommend the LifeStraw Go as a backup that you can carry around with you in addition to a more affordable primary unit, like Sawyer Mini.

Pros:

• Convenience

Cons:

• Smaller pores make it harder to suck
• Cost

Best Water Filter for Small Groups

MSR Guardian Military-Grade Water Purifier

Originally designed for the U.S. Military, the MSR Guardian Military-Grade Purifier is a top-of-the-line purifier that will live up to your requirements whether you’re on a camping trip or in an apocalypse bunker. This unit gets rid of bacteria, protozoa and is one of the few pumps that can eliminate viruses, as well. It is, perhaps, the best water filter on this list.

Portability and ease of use: The MSR Guardian is a little on the larger side at 17.3 oz and measuring 8.5 inches tall and 3 inches wide, but not to a point that it’s unreasonable.

You can use the Guardian by simply dipping the inlet tube into a water source and pumping. One thing you should keep in mind is that the output water comes out of a large mouth that screws onto erm… large-mouthed bottles like ones from Nalgene, or MSR Dromedary and Dromlite bladders.

Filter rating and maintenance: A 0.02 micron takes care of bacteria, protozoa, and even viruses (not too common with pump filters). It also has a high flow rate of 2.5 liters (0.66 gallons) per minute, making it ideal for small groups of people. You can even split the work of pumping that way.

But, why I really recommend the Guardian is because of its unique self-cleaning function that uses 10% of inlet water to backflush itself with every stroke – you don’t have to remove and scrub the filter yourself!

Durability: As I mentioned earlier, the Guardian was made for the military and, unsurprisingly, is one of the best-built units in the market. MSR claims that it can survive a 6-foot drop, and is resistant to high heat and freezing.

However, some users have experienced issues with the pin-piston element in the pump, so I recommend that you use it at home when you get it, to ensure it works well.

The tiny 0.02-micron fiber, meanwhile, is good for about 10,000 liters (2,640 gallons), and MSR does sell replacement filters separately.

Cost per gallon: The MSR Guardian will end up setting you back about $0.13 for a gallon, which is a considerable amount of money. The price tag of the product may just be one of the biggest factors that turn you away from buying the Guardian.

Verdict: The MSR Guardian is a great product but it may be overkill for most instances. The Guardian’s heft is also something you should consider if you want to carry as little weight as possible. That said, it can also serve as the only water filter you’ll need with its impressive purification capabilities.

Pros:

• Self-cleaning function
• Removes viruses
• Replaceable filters.

Cons:

• Heftier than alternatives
• No adapters or hose for narrow-necked bottles

MSR MiniWorks EX

The MiniWorks EX is another product from MSR that’s ideal for smaller groups. It’s a lot more affordable than the Guardian but does not come as equipped.

Portability and ease of use: The MiniWorks EX weighs 16 oz and is 7.5 inches long. It’s not the smallest of water filters, but it is one of the more compact pump units out there. The weight, however, is on the higher side.

In terms of operation, it’s quite similar to the Guardian above – you dip the inlet tube into a water source and pump. Just like the Guardian, this one, too, sends the filtered water out via an exit that is compatible with wide-mouth bottles and pouches. Some examples are Nalgene bottles, or MSR Dromedary, and Dromlite bladders.

A downside is that the flow rate is quite low, so if you’re not the kind that likes to stop and smell the roses and wants to move as quickly as possible, this isn’t the unit for you.

Filter rating and maintenance: The MiniWorks EX has a filter that is rated 0.2 microns – its pores are 10 times larger than that on the Guardian. However, this is standard for most pump filters at the price range and is sufficient to block out sediment and bacteria.

The ceramic filter on this unit is also capable of filtering out some amount of metals and chemicals thanks to its ceramic core. How likely are you to run into water that’s chemically polluted? Not very. But it’s a nice feature to have.

Keep in mind that this filter does clog up quite easily, but you can remove it from the unit and clean it, easily.

Durability: The filter on the MiniWorks EX is good for 2,000 liters (528 gallons), which is a decent amount.

Build quality is impressive as well and you’ll get by even if you aren’t extremely careful with it.

Cost per gallon: Each gallon filtered on the MiniWorks EX works out to above $0.17, which is again, on the higher side. However, similar products – concerning filter rating and size – like the Katadyn Hiker Pro, will work out to be more.

Verdict: While the MiniWorks EX is heavier than some of its rivals, it offers the additional benefit of metal and chemical filtering. It works great if you want to turn turbid, cloudy water from snowmelt or ponds into clear, drinkable water.

Pros:

• Activated carbon core filters chemicals and metals
• Easy to clean.

Cons:

• Heavy, pre-filter floats are easy to lose.

Best Water Filter for Large Groups

LifeStraw Mission Water Purification

If you’re going to bug out with a larger group of people (5 to 10), the LifeStraw Mission water purification should take care of your basic water needs. It is a gravity water purifier that has been designed to treat large quantities of water.

Portability and ease of use: The LifeStraw Mission is essentially a large bag with a filter that you suspend from a tree, or just about anywhere that will let gravity do its job. It’s available as a 5 liter (1.3 gals) option and as a 12 liter (3.1 gals) option, both of which you can fold up and pack away.

The bag does have a roll-top but it does not seal perfectly, so it’s not ideal if you’re planning on using it to carry water.

To set it up, just fill the bag with water, suspend it, prime the dirty water and air out via the red tap, and then use the blue tab to control the exit of clean water. You’ll also need a large collection reservoir!

Lifestraw claims that the Mission can produce up to 3 gallons per hour, but we’ve found that it usually produces about a third. This is acceptable considering all you have to do is fill it with water and hang it up.

Filter rating and maintenance: The Mission comes with a 0.02-micron filter. By now you should know what 0.02 micron means. Yup, virus filtration. The LifeStraw Mission is one of the very few gravity fitters out there that has a 0.02-micron filter. It also has a pre-filter that removes sediments and larger particles.

The post-filter, on the other hand, is similar to the LifeStraw personal straw that we saw earlier in this article but has a backflushing system to clear build-up.

Durability: The filter that the LifeStraw Mission uses is good for 4,755 gallons.

The LifeStraw Mission pouch, meanwhile. is made of a durable BPA-free plastic compound, but it’s still not the best. Many consumers have complained of leaks, especially since you have to roll it up every time you use it.

Another downside is that it’s not the best filter for colder regions as any leftover water in the pouch will freeze, and prevent you from using it.

Cost per gallon: The cost per gallon for the LifeStraw Mission works out to a fairly decent $0.02 per gallon.

Verdict: The LifeStraw Mission has its flaws, but it’s still our pick for an easy-to-use filter that serves larger groups of people. If you can stretch your budget, we also suggest you take a look at the Berkey BK4X2 Countertop unit. It’s better put together and has a faster flow rate but is significantly more cumbersome to lug around if you’re hiking.

The MSR Autoflow is another popular option, but it comes with only a 0.2-micron filter and a 4 liter (1 gal) bag.

Pros:

• Can filter viruses
• Easy to use.

Cons:

• Slow flow rate
• Prone to damage.

HydroBlu Go Flow Gravity Kit

If you’re not willing to spend nearly a hundred bucks on the LifeStraw Mission, then the HydroBlu Go Flow may be your best bet. It’s not as capable, but it’s nearly half the price and just as simple to use.

Portability and ease of use: The HydroBlu Go Flow Gravity kit comprises two components -a 10 liters (2.6 gals) pouch and the company’s best inline filter, the Versa. The pouch rolls up into a small pouch, adding up to 8.78 ounces. The filter, on the other hand, is 7 inches long and weighs just about 10 ounces. No problem, then, to carry around.

Just like any gravity filter, you fill the bag with water and suspend it, allowing it to do the work. Note that while the bag has a 10-liter capacity, you should fill it with about 8 liters.

Filter rating and maintenance: The Versa filter has a 0.1-micron rating and this means that it cannot filter out some viruses. However, it does a good job at removing bacteria, protozoa, and sediments.

The filter also has an easy-to-use backwashing system that makes it quite simple to maintain.

Durability: While the company hasn’t revealed an exact figure for its life, we suspect it’s anywhere between 20,000 gallons to 100,000 gallons. We’d recommend this filter, even without the bag, if you’re looking for an inline filter option.

The pouch, too, is of decent quality, and consumers have reported that it holds up even after several uses.

Cost per gallon: At about $0.002 gallon, the Go Flow Gravity kit offers great value for money.

Verdict: If you want a budget fitter for larger groups, this is the one for you. The Sawyer Gravity system – which uses the Sawyer Mini – costs almost the same, but the bag is of inferior quality.

The MSR Autoflow and Platypus GravityWorks, on the other hand, are popular options that cost nearly $80-130 more.

Pros:

• Durability
• Large reservoir size
• Decent flow rate.

Cons:

• Not ideal in colder regions

You can get yourself the Go Flow gravity bag and HydroBlu Versa Flow filter, separately, or buy the kit that includes both.

Different Kinds of Survival Water Filters

Based on the way they work, water filters can broadly be classified into three main types – Inline filters, gravity filters, and hand pump filters.

Inline filters: Inline water filters are small, portable tubes with a filter inside them. They can be used as a straw to drink directly from a water source or screwed to the hose of a hydration bladder or compatible water bottles.

They’re extremely versatile and if you had to choose just one, this would be the kind I’d recommend. One thing to keep in mind is that, since they work on a rather simple principle, most inline water filters are incapable of filtering out viruses.

Gravity filters: As the name suggests, gravity filters work with, well… gravity. They usually comprise an inlet reservoir with an inline filter inside, or in the output hose. You pour water in from above, and gravity does the rest of the work – it passes the water through the filter, and you get clean water out the other end.

Gravity-based filters aren’t the best in terms of portability as they have to be set up like you would in a camping context. On the flip side, they are capable of producing large quantities of water with the least amount of effort.

Hand pump filters: I like hand pump filters because you don’t have to use your mouth to filter water. They also work best when there’s a shallow source of water, like a puddle. You can filter as much water as you want, as long as your hand can keep pumping.

The advantage of most hand pump filters is that they use a ceramic material for their filters. These filters require to be removed and scrubbed clean. Now, that sounds like a task, but it’s a good thing because you can see how much life is left in the filter. The downside to one is – you guessed it – you can’t rely on gravity to do the work.

When and Why Do You Need an Emergency Water Filter?

Alright, any sane prepper or survivalist will attest to the fact that having a water filter handy is priority number one. Large-scale emergencies, like an industrial accident, hurricane, flood, and any SHTF event, can result in the immediate contamination of water.

To give you an example, when Hurricane Harvey tore into Houston in 2017, it contaminated the water so badly that people were falling ill just by walking in it. Tests indicated that the water had about 5,700 times more bacteria, from fecal matter and sewage than EPA standards.

And in a time of emergency like that, you don’t want to be feeling ill or fatigued.

Emergency water filters are essential for your survival kit as they’re portable, eliminating the need to store water, easy to store, and most importantly, efficient.

Conclusion:

A family of four needs about 12 gallons of water a day for the body to function optimally. Whether you choose to reach that goal with each of your filters, or one larger unit that does its job for all of you, is something you have to decide.

Hopefully, this list has helped you figure out what works, what doesn’t, and how you can go about putting together the right water filtering kit to keep you and your loved ones safe through an emergency.