The Best Water Filters for Travel 2023 + Everything You Need to Know

If you are planning a trip or outdoor adventure to a destination where the local water might not be safe for drinking, you might be considering packing a water filter. This might be a backcountry camping trip, a hiking trip, or a trip overseas where you aren’t sure if the tap water is safe to drink.

Whatever the reason that you are thinking about packing a water filter, this post will help. We’re going to cover everything you need to know when it comes to choosing a water filter for travel, and also suggest the best water filters for your trip.

We’ll go over what a water filter is and why you might need one. We’ll look at what water filters actually remove from the water, and the different methods they use for doing so. We’ll cover a range of features that a water filter might have, and which ones you should consider important for your trip.

We’ve used a number of different water filters on our travels, both on camping trips in the back country and on trips to countries where the water wasn’t safe to drink.

We’ve put this guide together based on our personal experience as well as extensive research using information from trusted sources like government agencies.

By the end of this post, you should know if you need a water filter for your next trip, and if so, which one is going to meet your needs and budget!

Why You Might Need to Filter Your Water

Before we get into specific water filters, let’s look at why and where you might need to treat the water you are drinking.

As humans, we need water to survive. General guidelines are to drink 6 to 8 8oz glasses of water per day. The exact amount required varies depending on a range of factors, including ambient temperature and our level of physical activity. A lack of water can quickly become lethal, with most experts agreeing that the human body can only survive a few days without water.

So, we definitely need water. Unfortunately, water often contains things that are not good for us. These can include bacteria, viruses, and parasites as well as chemicals and metals.

Some of these may cause mild to moderate illnesses like travellers’ diarrhoea (or travelers’ diarrhea). This is actually the most common ailment travelers are likely to suffer from. Others can lead to very serious illness and even death. As such, it is important to ensure that the water you are exposed to is clean and free of any harmful contaminants.

This includes drinking water, and also the water you use for brushing your teeth, as ice in drinks, for cleaning fruits and vegetables, amongst other things. It only takes a small amount of contaminated water to cause a serious issue.

The main reasons people use water filtration devices are to filter potentially unsafe water for drinking, cooking, and personal hygiene. Common situations where you might need to filter water are as follows:

When hiking, camping, fishing, boating, and backcountry travel where you may be drinking untreated water
International travel to destinations with unsafe drinking water
Situations, such as flooding or water treatment issues, that make home water supply unsafe
As an environmentally-friendly alternative to buying and drinking bottled water
To filter safe but bad tasting water

Now, there are a number of different ways that you can treat water, as outlined by the US Centers for Disease Control and Prevention here. These include boiling water, using chemical treatments, filtration methods, and the use of UV light. So you do need to make sure that you are using the best method based on the type of contaminant, the destination, and your travels.

We discuss all these methods in more detail in our guide to accessing safe drinking water when traveling. That guide also covers things like how to know if you need to filter water, and where tap water is safe to drink. We would recommend reading that guide as well for a fuller understanding of the topic.

This guide will focus specifically on water filtration as a method for treating water. In this guide we will be primarily looking at water filters from a travel perspective, meaning devices that are designed to provide you with drinkable water on trips abroad, hiking, back country camping trips, etc.

What is Water Filtration?

Water filtration is a method of purifying water for drinking. In the case of water filtration for travel, the goal is to make it safe to drink. There are other water filters on the market, often marketed for in-home use, which are primarily designed to remove taste and odor from water, but those are not within the scope of this guide.

Water filtration devices are a popular option for making water safe to drink when traveling, with a number of options available on the market at varying price points. Water filtration works by passing the water to be treated through a fine filter. The filter pores are so fine that they remove many contaminants from the water, resulting in clear, drinkable water.

Generally, the size of the filter pores will determine which contaminants the filter is capable of removing. Filter pores of around 0.1 – 0.2 microns (100 or 200 nanometres) will filter protozoa and bacteria, but not viruses. To filter out viruses, the CDC recommends filtration pores smaller than 0.03 microns (30 nanometers).

There are other technologies that can be used as part of a water filter such as ion exchange technology which can also purify water of various contaminants. These usually work in combination with pore-based technology.

A good water filter will clearly list what it is capable of cleaning, and should also reference the certification standards it has met that allow it to make these claims. More on these standards later on in the post.

Some water filters also include a carbon filtration stage which is designed to remove bad tastes from the water.

Advantages and Disadvantages of Water Filters for Travel

A water filter can be a good option for travel, but it is not the only option.

Some of the advantages of water filtration over other water treatment methods include:

They can filter lots of contaminants, including bacteria and protozoa. Some can also filter viruses.
They can filter water in a shorter amount of time than most other methods – almost instantly in certain types of filters such as the straw ones
They are able to remove cloudiness caused by dirt/silt/sand, producing clear drinking water
They can enhance the taste of water with carbon filtration
The filtration device also often acts as a drinking vessel and for water storage, meaning you can carry some water with you
They do not require any sort of energy source to work, meaning they are effective even when off-grid
They are a lightweight option compared to something like a camp stove
Some filtration systems, particularly gravity-based filtration, are ideal for cleaning large amounts of water which is good for a group scenario

Some of the disadvantages of water filtration over other water treatment methods include:

The upfront costs can be higher than some other methods, although over time this cost evens out
Most systems have filters which need replacement, adding to the overall cost
They are more bulky than some options such as chemical filtration tablets or drops
Some effort/force is needed on some methods of filtration, including pump-based and straw-based filtration methods
They are not as effective on certain types of contaminants as boiling

Overall, a water filter can be a great option, but it is not the only one. See more options in our guide to safe drinking water for travel.

What to Look for in a Travel Water Filter or Purifier

Before we go through some of our recommended water filters, we wanted to cover what you should be looking for in a water filtration device.

What can a Water Filter Remove?

Probably the most important question you need to ask when shopping for a water filter or purifier is what it is capable of removing from your water.

The main contaminants you are likely to want to remove from water are:

Viruses
Bacteria
Protozoa
Parasites
Chemicals
Metals
Dirt / silt / sand
Microplastics

While water filtration and water purification systems are able to remove the above types of contaminants, not all filtration systems are capable of removing all these contaminants from water. To choose the best water treatment method, you will want to consider where you are traveling and the sorts of water sources you are likely to have access to.

Most water filtrations systems can remove most dirt, sand, microplastics, bacteria, protozoa, and parasites from the water. However, only those with finer filters will be able to handle viruses as well. And only those with carbon filters will generally be able to remove chemicals affecting the taste or smell of the water.

For backcountry travel in the US for example, the more pressing concerns are protozoa and bacteria, which most water filters should be able to handle. Viruses are most commonly transmitted via human waste, and this transmission is far less common in the US due to good waste management practices and low population densities in the areas where travelers might need to filter water sources.

Travelers to developing parts of the world may also want to consider a water purification system that can also remove viruses. Of course, those of you wanting to err on the side of caution (not a bad thing), might want a full purification system regardless of destination.

What can’t a Water Filter Remove?

Water filters and water purifiers can’t remove every possible type of harmful contaminant from water. You will want to carefully read the specifications of a particular water filtration product to ensure it removes the contaminants of concern for you.

It is important to note that water filters are generally NOT capable of removing things like:

Fuel oil
Toxic chemicals
Radioactive materials

In scenarios like this, which normally are disaster related, the CDC recommends using bottled water.

Water filters for travel are also not designed to desalinate or filter seawater or ocean water.

Water Filter vs Water Purifier

You may come across the term water filter and the term water purifier, and wonder what the difference is. The difference is normally down to what it removes from the water.

A water filter is normally capable of filtering out protozoa and bacteria, and has larger pore sizes in the filter mesh. A water purifier can also filter out protozoa and bacteria, but is additionally capable of filtering out viruses which are much smaller.

Travellers in the United States will normally be more concerned with bacteria and protozoa such as Giardia and Cryptosporidium, which can be filtered out with a water filter. Travelers to less developed nations will need to consider viral risks like hepatitis A, which require a purifier.

These two types of filtration products are normally grouped together and we will be covering both of these products in our guide.

What Filter Mechanism Does It Use?

Water filtration devices, as the name suggests, use a filter to clean the water. These filters are very fine, and the water normally needs some pressure in order to pass through the filter itself.

Different filter systems have adopted different approaches to this. Three common systems are straw-based, pump-based, and gravity-based.

A straw-based system works like a drinking straw. The filter is found inside a large drinking straw like device. You put one end of the straw in the water to be filtered, and suck on the other end. The action of sucking through the straw creates negative pressure which results in the water passing through the filter and into your mouth. This is a good option where you have regular access to water, but is best suited for single person use. It can also require quite a lot of effort to suck the water through the straw.

Examples of recommended straw-based filtration systems are the LifeStraw Go and Sawyer Bottle.

A pump-based system works using some kind of pump to exert pressure on the water and force it through the filter. This is a good option for filtering water for later use, and you can filter as much or as little water as required in the moment. The disadvantage is that it can require quite a lot of manual effort to filter the water.

Examples of popular pump-based filtration systems are the Survivor Filter Pro and Grayl UltraPress.

A gravity-based system uses gravity to force the water through the filter. You add the water to be filtered to a bag, hang it up somewhere with the filter at the bottom, and gravity causes the water to pass through the filter. This can take some time, and is more popular for larger amounts of water. This is a good option for a group camp or for RV use where you want to filter larger amounts of water for multiple people.

An example of a popular gravity-based filtration system is the LifeStraw Mission.

How Long Does It Take to Filter Water?

When evaluating a water filtration or purification system, you should investigate how long it takes to filter the water. In most cases, manufacturers should provide an estimate for how long it takes to filter a certain amount of water, say one litre or one gallon.

For example, a gravity or pump-based system might be capable of filtering 10 litres in one hour.

For a straw-based system, the speed will depend on how hard you suck on the straw. But filtration is fairly instantaneous.

How Easy is it to Use, Maintain, Clean and Store?

When it comes to a product that is designed to create safe drinking water, you ideally want it to be as easy to use as possible. We recommend looking at the instruction manual for any product to get a feel for how many steps are involved in producing clean water.

If a product has a complicated, multi-stage process, there is a higher likelihood that you are going to get something wrong, potentially leading to drinking contaminated water. Ideally, the process should be simple and easy to remember.

As well as ease of use, you will also want to consider how easy the product you choose is to maintain, clean, and store. It should be easy to take apart for any cleaning, and there should be guidelines on how best to store it between uses.

A water filter isn’t something you are likely to be using every day, so between trips you want to be sure it is something you can pack away for next time without worry.

How Much Water Can it Filter?

Most systems for water filtration and purification have a limit on how much water they can filter. Larger pore filters, such as those designed to remove bacteria and protozoa, tend to have a longer lifespan than those with smaller pores which are designed for viruses.

So for example, a purification filter that can filter out viruses might be able to do 100 – 400 litres before the filter needs replacing. A system for bacteria might be able to do 1000L+ before it needs replacing.

This is because the way the filters work is that they actually get blocked up by the stuff they are filtering out of the water. Over time, all the pores will be blocked and the filter will stop allowing water through. Smaller pores get blocked quicker than larger pores.

Some filter systems allow you to extend the life of the filter by “back-washing” them. This involves forcing purified water through the filter in reverse to clean it out. This can significantly extend the lifespan of the filter.

Some water filter systems have different filter stages as well. For example, there might be a pore-based filter for filtering out nasties, and a carbon-based filter for improving the taste. Often, the carbon-based filter will have a more limited lifespan. The good news is that a worn-out carbon filter doesn’t make the water less safe to drink, although the taste of the water might be degraded when it is worn out.

The main thing is to figure out how much water you are likely to need to filter on your trip, based on duration and number of people. Then you can see if the device you are choosing will be adequate, and if you might need to invest in additional filters.

How Durable Is It?

Depending on where you plan to use it, a water filtration system is likely to be a critically important part of your kit. Having access to clean water is really important, and you need to be able to rely on the product you are buying.

Ideally the product will have been tested to withstand a certain amount of impact, both empty and full. If it stores water, you want to be sure it’s not going to leak. Out on the trail, you want something that is going to be able to handle being dropped or bashed around a bit without failing.

Definitely be wary of anything that has small fiddly bits of plastic that might easily break, as this could cause a serious problem. We would normally recommend having a fall-back system, such as chemical purification tablets if you will be off-grid for a while, just in case.

How Much Does It Weigh?

Weight is an important consideration for any traveler. If you are planning a back country hiking trip where you are carrying everything on your back, then you will definitely be thinking about weight a great deal.

However, even travelers with checked luggage don’t have infinite luggage allowances! So you are unlikely to want to pack a big bulky water filtration system, or carry it with you when you are out sightseeing.

The good news is that many of the options on the market are lightweight and designed to be portable, often being not much larger or heavier than a normal water bottle.

Does it Have Replaceable Parts?

Different filter designs will likely have different parts that are replaceable, and it is worth understanding what these parts are and what the replacement costs are.

Most filter systems will have replaceable filters, but some may have additional elements like hoses or seals that you are able to replace.

When comparing prices of different systems, it is worth checking the different prices of these replacement parts and their estimated lifespan so you have an idea of a total lifetime cost.

Certification of Efficacy

For something as important as safe drinking water, it is not enough to believe a manufacturer’s claims of efficacy. Any producer of a water filtration or purification system that believes in their product should be willing to have it independently tested to an agreed standard. Ideally these tests will be provided in full for you to look at.

There are two main standards that are used for water purification / filtration testing. The first is the EPA standard. This was developed by the US-based Environmental Protection Agency in the 1980s, and provided a framework for testing micro biological water purifiers in order to demonstrate if they produced water that was safe to drink.

A more recent testing framework, NSF P231, was released by the international organisation NSF (this used to stand for National Sanitation Foundation, but today it is just called NSF). The NSF framework was developed based on the EPA document, but is regularly revised and updated.

NSF P231 is the standard you should be looking for as a minimum for filtration testing. It is a tough 10-day test in multiple parts, and a reputable manufacturer should be able to show evidence that their device passed the test in full.

It is worth noting that there is also an even more strict standard, NSF P248, which some brands also test to for extra peace of mind. This is similar to P231, but was developed for testing US military water purification systems for use on military operations. This one is less common for consumer-focused filters, but if you want the ultimate in peace of mind, consider investing in a product which has met P248 testing requirements.

Note that there are other NSF testing standards, including NSF 42 and 53. These are primarily designed to test home water filters for taste improvements, rather than to render them safe.

We would definitely recommend investing in a filter that meets EPA and NSF P231 testing standards, and which provides proof of the same.

Cost Per Litre / Gallon

When you are comparing different water filters and purifiers, it can be hard to get an idea of how they compare from a cost point of view.

One good way to compare is to see how much it would cost you to filter one litre or one gallon of water using the device. To do this, you just need the cost of the device and the amount of water it can filter over its lifetime.

For example, you might spend 100 dollars on a device that can filter 1,000 litres of water. 100 divided by 1,000 is 0.10. So this device would cost you 10 cents per litre.

Of course, if the device has a replaceable filter which costs 25 dollars, your future cost will drop. So over the total lifetime of the product your overall cost might be lower. However, calculating the initial cost per litre or per gallon is a good starting point for comparison purposes.

What Water Sources Does It Support?

Depending on the type of travel you are doing, you might need a different style of water filtration device. For example, if you are primarily travelling in a country where you just want to filter the tap water for safety, then most devices will work fine as you can just hold them under the tap.

However, if you are planning a back country trip that will require you to source water from a stream or river, then you will need a device that allows you to capture that water, especially if the source is shallow. This might involve tubing and a pump, or some other mechanism for capturing the water to be filtered.

The main thing is to pick a device that is capable of working in the various scenarios you will need to use it in.

What Temperatures Does It Work In?

It is really important to check what temperatures the device you plan to buy is capable of working in. This is especially the case if you are planning on traveling to a cold weather destination.

When the temperature dips below freezing, obviously this can cause any water inside your filtration system to freeze. Some filters will be permanently damaged if this happens, and so are not rated for use in freezing weather conditions.

Most devices will work fine in warm weather, although do always check what temperature range the device is rated for and compare it with the temperatures you expect to encounter when using it.

The Best Water Filters for Travel

We will now go through our pick of the best water filters for travel. We list products across a number of water capacity sizes and price points that will suit a variety of travelers’ needs. We include water filters and water purifiers that use each of the three primary filtration methods.

Before we do though, a quick note. We are not qualified water purification experts or medical professionals, and you should seek professional guidance as to the best water filter for your needs and specific situation. This article is for information purposes based on our experiences, and does not constitute health advice.

We would stress that water purification is a complex topic, and drinking water that is not properly treated can be life threatening. So please ensure you research the topic thoroughly, understand the risks for your needs and destination, and get qualified advice if you are unsure.

These products are grouped by filter type (straw, gravity and pump), and then approximately by price, although prices vary so do compare before making a decision.

LifeStraw Go

LifeStraw are a well-known brand in the world of water filtration. They make a range of products, some designed for large scale water filtration in developing countries, others that are focused on the needs of travelers specifically.

Our favourite LifeStraw product for general travel is the LifeStraw Go. We’ve used this on back country hikes in the USA where there hasn’t been filtered tap water available, including on a multi-day hike to Havasu Falls in Arizona. We’ve also taken it on international trips to filter tap water.

The LifeStraw Go is a combined water bottle and water filter. It uses a straw-based filter system. To use it, you fill the bottle with the water you want to filter. The lid has a removable large straw filter attached to it, and when you suck through the spout in the lid the action of sucking draws the water through the filter.

There’s are various sizes available, including a 650ml (22 fl oz) version and a 1 litre (34 fl oz) version, and it can be purchased in either a stainless steel of BPA free plastic version. You can also buy a straw standalone if you don’t want the bottle.

The product uses a 0.2 micron filter which is capable of filtering out bacteria and parasites, but not viruses. It can handle up to 4,000 litres (1,000 gallons) before the filter needs to be replaced. It also has a carbon filter to improve the taste, however this is only good for 100 litres (26 gallons) before it needs to be replaced.

LifeStraw test all their products and publish their results on their website. The LifeStraw Go meets US EPA and NSF P231 drinking water standards for the removal of bacteria and parasites.

The main disadvantage of the LifeStraw is that it is really designed for single person use. The filtration happens as you drink, so you can’t filter water and then distribute it to others. So everyone would need their own LifeStraw. It also isn’t good for filtering water for uses other than drinking, for the same reason.

However, as a drinking water filter it works very well as long as you don’t need to remove viruses, and the price is also very reasonable. We still use ours regularly when we travel.

Other similar options on the market include the Sawyer Bottle and the Katadyn BeFree. These work in a similar way, so you might want to compare stats and prices to see which fits your needs best.

Capacity: 650ml / 22fl oz
Weight: 221g / 7.84oz
Filter type: Straw based
What it can filter: bacteria, parasites
Lifespan: 4000 litre / 1000 gallon
Cost per litre in USD at MSRP: 1 cent per litre
Price: Check online at Amazon here, REI here

Sawyer Bottle

Sawyer are another well-known brand who make a variety of water filtration products. The Sawyer Bottle is similar to the LifeStraw Go in that it works with an inline straw. To use it, you simply fill up the water bottle, then drink through the inline straw.

The bottle uses Sawyers 0.1 micron filter technology, which means it filters out bacteria and parasites, but won’t remove viruses. As it’s a straw, you need to suck quite hard to get the water through.

One major advantage of the Sawyer Bottle compared to the LifeStraw Go is that it comes with a backwashing kit. This is basically a syringe that you can use to force clean water through the filter in reverse, a process known as backwashing.

This significantly extends the life of the filter because it unblocks the pores. Sawyer state that with regular backwashing (after every trip ideally), the filter should last for at least 100,000 gallons. That is basically a lifetime of use for most people, and it makes the Sawyer Bottle one of the most cost-effective water filters in our round up on a cost per litre basis.

The bottle itself is also relatively lightweight, at 5.5oz (155g), and can hold 34oz (1 litre) of water.

It has similar downsides to the LifeStraw Go, in that it is primarily designed for providing clean drinking water for one person, rather than water for multiple people or for other purposes like cooking.

It is also missing a charcoal filter, so does not remove the taste that filters with a charcoal filter do. Products are tested to EPA standards, with test reports available on their website here.

Capacity: 1 litre / 34oz
Weight: 155g / 5.5 oz
Filter type: Straw
What it can filter: bacteria, parasites
Lifespan: 454,609 litres / 100,000 gallon
Cost per litre in USD at MSRP: 0.01 cents per litre
Price: Check online on Amazon here

LifeStraw Mission

If you are looking for a product that can filter water for a number of people as well as for multiple uses, then consider the LifeStraw Mission. This is a gravity bag with a built-in filter.

To use it, you fill the bag up with water to be filtered, hang it up, and then gravity forces water through the filter and out of the tap.

This makes the LifeStraw Mission ideal for camping in groups, as well as general activities where you need water for multiple people or uses.

LifeStraw actually make a range of gravity style filters. The Mission is the version designed to purify water, and it will remove bacteria, viruses and parasites. This higher level of filtration makes it a more expensive option.

It meets NSF standard P231, and LifeStraw publishes lab report data on their website for their products.

LifeStraw also have other gravity products, such as the LifeStraw Peak and Flex, which are lower cost options that remove bacteria and parasites but not viruses. So which is best for you will depend on your destination and requirements.

If you want purification that can handle viruses as well, then the Mission is a good option. It comes in two versions, one with a 12 litre (3.1 gallon) bag and one with a 5 litre (1.3 gallon) bag. They both have the same filter, which has an impressive lifetime filtration capacity of 18,000 litres (4,755 gallons).

It’s also relatively light at 530g (18.7 oz) for the 12-litre version, which makes this a good option for travel. Given the long lifetime of the filter, it also offers an excellent cost per litre.

Capacity: 12 litres / 3.1 gallons
Weight: 530g / 18.7 oz
Filter type: Gravity based filter
What it can filter: bacteria, parasites, viruses
Lifespan: 18,000 litres / 4,755 gallon
Cost per litre in USD at MSRP: 0.7 cents per litre
Price: Check online on Amazon here and REI here

Grayl UltraPress

We came across the Grayl range of products when researching a trip to Africa. We didn’t want to have to be constantly buying bottled water, but knew that the risk of water borne viruses was a real concern. As such, we wanted a filtration system we could rely on to fully purify water for drinking.

In our case this was primarily going to be water sourced from taps, so whilst it was normally clear to the eye, we had no idea what it might be carrying. To be on the safe side, we figured a system that filtered out everything including viruses was a good idea, which meant our LifeStraw Go wasn’t going to cut it.

We found the Grayl UltraPress met our needs. This looks like a water bottle, but has a clever built in-filter system which has you pressing the filter through the water sort of like a French Press, with the clean water ending up in a chamber you can drink from.

There are a few advantages of the Grayl UltraPress. First, it is capable of filtering out all waterborne pathogens including viruses. It does this with a combination of small pore holes and electroadsorption / ion exchange. There is also a carbon element in the filter to remove taste and odor.

Second, the press system means that the purified water goes into a chamber from where it can be decanted into other containers. So you can use this for multiple people, for cooking, personal hygiene and so on. This makes it much more flexible compared to a straw-based system.

There are some downsides. The double-walled design and relatively large filter unit means that the device is a little heavy. It can also only hold 500 ml / 16.90z, although the larger GeoPress model holds 740 ml / 24oz

In addition, a filter which can filter out viruses often has a shorter lifecycle.

The Grayl Ultrapress filter is rated at 150 litres (40 gallons), so the cost per litre is quite high. In some destinations, it might even be higher than buying bottled water. However, replacement filters are not too expensive, so over the lifetime of the product the price per litre will come down a little.

The larger GeoPress is only marginally more expensive and can do up to 250 litres (65 gallons) per filter, so that does work out more cost-effective overall. However it is also bulkier and heavier.

Pressing the water also takes a bit of effort. I found it easiest to put the whole unit on the floor and then push down, although it can be done by hand on a table as well. Grayl does recommend using your body weight to push it down, and the surface of the top of the bottle that you push on is designed to be comfortable to do this and to withstand the pressure.

It’s just quite a bit of work, and in my experience took a little longer than the 10 seconds Grayl suggests, even with clean water and a new filter.

It is also worth noting that an electroadsorption / ion exchange based filtration process is a little different to standard filtration which relies on pore size. A pore-based system basically blocks the bad things. An ion based system works a bit like glue – the bad things in the water like viruses stick to the ions while the water passes through.

Unfortunately, over time, the ions can lose their charge and the filter can lose its effectiveness. Unlike a pore-based system, which blocks up and becomes un-usable when exhausted, there’s no easy way to tell when an ion-exchange system has lost its charge.

Grayl state that 300 presses is the lifetime of the system, and this is when the larger pores will become blocked, resulting in reduced flow. Basically, when it takes twice as long as normal to press through, it’s time to change the filter. We’d recommend trying to keep track of how much you have used it as well, and erring on the safe side when it comes to replacing the filter.

Finally, whilst the Grayl website states that the product has been independently tested to meet or exceed NSF protocols 42 and 53, there is no mention of NSF protocol P231, which is the standard that should be tested to. I also wasn’t able to find the test results on their website.

I did reach out to Grayl about this, and they did send through independent laboratory test reports that show that the product works as advertised to remove viruses, bacteria and protozoa. So if you have concerns, I’d suggest reaching out to them directly, their customer service is very responsive.

In addition, independent tests like this have shown that Grayl does purify water as it claims. I would like to see this sort of thing published on the Grayl website for transparency.

Overall we have liked our Grayl UltraPress for travel.

Capacity: 500 ml / 16.9 fl oz
Weight: 354 g / 12.5 oz
Filter type: Electroadsorptive ion exchange / charcoal
What it can filter: bacteria, parasites, viruses
Lifespan: 150 litres / 40 gallons
Flow Rate: 3 litres / minute
Cost per litre in USD at MSRP: 60 cents per litre
Price: Check online at Amazon here, REI here and Grayl here

LifeSaver Bottle

LifeSaver was developed by a UK based inventor, and their products have been used by the British Army for water filtration in the field.

The LifeSaver Bottle is designed to filter out bacteria, viruses, and parasites. It works using an integrated pump and filter system. So you fill up the chamber, then use the built-in pump to pressurize the bottle.

This forces water through the filter, which uses 0.015 micron (15 nanometer) pores to purify the water. Clean water is then available in the clean water area, which can be used for drinking as well as other uses like personal hygiene and cooking.

The LifeSaver bottle has a relatively high up-front cost; however the 4,000 model is capable of filtering 4,000 litres of water before the filter needs to be replaced. This is a lot for a pump-based filter that removes viruses, and it means that the overall cost per litre is relatively low.

Because the LifeSaver is filter based, the pores will block over time, and when it is no longer filtering properly it will no longer allow water through.

There is also a carbon filter for removing taste from the water, and this has a lifespan of 250 litres.

In terms of specifications, the device has been tested to meet the NSF P231 standard as well as the more strict NSF P248 standard. The LifeSaver website lists test results for their products on their website here, with the most recent report we could find from 2020 showing the bottle met NSF P248 requirements.

You can also see an older test report performed by the London School of Hygiene & Tropical Medicine here. It’s good to see these test results shared publicly.

There are some disadvantages to the LifeSaver that are worth mentioning. As this is a pressurised system it is really important to follow the instructions carefully so as to avoid over-pressurising it, which can result in failure.

Additionally, the device needs to be primed, and to have an inch of water in it at all times, even when it is stored. Without the water, the pores close up and the filter stops working. It is possible to fly with the LifeSaver, and remove the water for a short period of time, but you need to remember to add water after the flight.

This is also a fairly heavy overall solution compared to other options on our list. LifeSaver do have a newer product called the LifeSaver Liberty, which weighs 425g (15oz), and which can filter up to 2,000 litres (440 gallons). Being smaller, it can only store and process 400ml (13.5 fl oz) at a time. However, if weight is a primary concern, then that would be our recommendation.

If you need more water storage and processing capacity, then consider the LifeSaver Expedition Jerrycan. This is also rated to NSF P248, and can store and filter up to 18.5 litres (4 gallons) of water at a time. It is available in two versions, one with a filter that can handle 10,000 litres (2,650 gallons), and one with an impressive lifespan of 20,000 litres (5,300 gallons).

The Jerrycan would make for an excellent option for those of you looking for a camping or RV solution where you have a vehicle and weight is less of an issue. It’s also a great option for disaster planning for at home use.

Overall though, the LifeSaver Bottle is a really good option if you would like filters with a long lifespan, virus removal with a relatively low cost per litre, and a product that has been tested to the highest standards. Just be aware that it is a little heavier than some other options, and you need to follow the instructions carefully.

Capacity: 750ml / 26.4 fl oz
Weight: 635g / 22oz
Filter type: Pump based filter
What it can filter: bacteria, parasites, viruses
Lifespan: 4,000 litre / 1,056 gallon
Flow Rate: 2.5 litres / minute
Cost per litre in USD at MSRP: 4.5 cents per litre
Price: Check online on Amazon here, REI here

Survivor Filter Pro

Survivor is another well-known brand for water filtration. The Survivor Filter Pro is popular with back country campers, but it’s a good travel option in general due to its light weight.

The Survivor Filter Pro is basically a hand powered pump filter. Unlike most of the other devices in our round-up, it doesn’t have built-in water storage. Like the SteriPen, it is designed to work with your existing water storage system.

The pump is quite simple. It has an inlet hose and an outlet hose, as well as three filter stages. You put the inlet hose into the water you want to purify, and the outlet hose into your container. When you pump, the water passes through the three-stage filter process.

These three stages work as follows. First, there’s a 0.1 micron (100 nanometer) pre-filter which removes bacteria and parasites. The water then goes through the carbon filter, which improves taste and can remove certain heavy metals and chemicals.

Finally, the water passes through the 0.01 micron (10 nanometer) ultra-filter. 10 nanometers meets the CDC guidelines for optimal ultrafiltration of viruses.

You might think that having such fine pores would result in the Survivor Filter Pro having a short lifespan. However, Survivor supplies you with a syringe that can be used to force clean water through the pump in reverse. This flushes out the filters, unblocking the pores, and greatly extending the lifespan.

With regular back washing, Survivor states that their filters will last up to 100,000 litres (26,417 gallons) before needing to be replaced. Replacement filters are also relatively low cost. The carbon filter is rated up to 2,000 litres (528 gallons).

In terms of testing, all Survivor Filters are tested by independent third-party labs to be sure they perform as claimed up to NSF standards. You can see the reports on their website here.

In terms of cost per litre and overall unit cost, the Survivor Filter Pro offers excellent value for money. The only main downside is the flow rate. It takes a minute to pump half a litre of water. This is honestly to be expected, given the very tiny pore size in use, but it is definitely one of the slower options on our list.

If you don’t want to spend your time pumping, consider instead the battery powered electric version. That will filter up to 360 litres (95 gallons) from two AA batteries, but can also be powered by USB. Of course, relying on an electric solution will not be for everyone.

Overall, as a lightweight long-lasting option this is a very good choice. It’s particularly good for backcountry camping where weight is key, and where turgid water sources might stump a UV based system like the SteriPen. You also obviously need to pack and bring your own water bottle.

Capacity: N/A
Weight: 362g / 12.8 oz
Filter type: Pump based filter
What it can filter: bacteria, parasites, viruses
Lifespan: 100,000 litre / 26,417 gallon
Flow Rate: 0.5 litres / minute
Cost per litre in USD at MSRP: 0.07 cents per litre
Price: Check online on Amazon here