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Boiling vs Filtering Water: Which is Better and Safer?

You’ve probably heard conflicting information about whether boiling or filtering water is safer or better. Water filter companies are preaching that it’s safer to filter your water, but the CDC advises boiling water is the “surest method to kill disease-killing organisms.” What does this mean, exactly?

We wanted to know, so we did a deep dive to understand the Boiling vs Filtering Water debate. As it turns out, both methods are effective, but if done correctly, one method can do something the other can’t.

Keep reading to learn the pros and cons of boiling vs filtering water and how you can stay safe and healthy while drinking, cooking, and brushing your teeth on your camping trips.

A camping water bottle with clear water inside. Boiling vs filtering water.

Using Safe Drinking Water While Camping

Drinking, washing produce, and even brushing your teeth with outdoor water sources pose a host of risks. This is especially true if you’re unaware of specific water-quality alerts in the area or if signs are not available indicating if water is safe to drink.

Our ancestors were able to link a connection between water quality and health in the early ages of time.

Water boiling treatments date back to the 15th Century B.C., with early literature describing the methods of boiling water over a fire, heating water in the sun, dipping heated irons into the water, and filtering the water through sand.

Historians have found writings from 2000 B.C. that reported water must be boiled, dipped with copper seven times, then filtered by exposing it to charcoal and sunlight.

Fortunately, water filtration has become much simpler thanks to modern technology.

The first water filter was patented in the mid-1700s by a man named Joseph Amy. Mr. Amy’s design was made from wool, sponge, and charcoal layers. Home water filters were made available by the 1750s.

Portable water filters for campers and backpackers would take some more time to become widely available. They first appeared in the early 1900s and did not gain popularity until the 1970s. Present-day portable water filters retain many of the same concepts as the first water filters.

Today, backpackers and campers frequently use portable water filters and purifiers, so they can safely brush their teeth, wash their vegetables, and stay hydrated without ever boiling their water.

The big question is, are these portable water filters safer than boiling water?

Know Your Water Source

The first piece of understanding boiling vs filtering water is to know why we must treat the water we find outdoors.

A clear camping water jug.

Contaminated water is commonly found in campgrounds, secluded areas, and foreign countries. These water sources are typically not treated. Campground water pumps often come from private wells, which are not regulated by the United States Environmental Protection Agency (EPA).

Even clear water can contain contaminants, so drinking water straight from the source is never a good idea without treating it yourself.

Contaminants Commonly Found in Water

The biggest piece to analyzing the boiling vs filtering water debate is knowing the type of contaminants you’re needing to remove from the water.


These contaminants are alive in the water, including bacteria, viruses, and parasites. These contaminants include some of the following:

  • E. Coli: This is a common bacteria caused by contaminated food or water. Healthy adults usually recover within a week, but young children and the elderly are at higher risk of kidney failure caused by the bacteria.
  • Norovirus: This is a common virus that spreads through water, food, and surfaces by infected individuals, commonly mistaken as the stomach flu. It usually lasts for 1 to 2 days and is very contagious.
  • Giardiasis: This is a parasite that is passed through stool. It causes greasy stools that float, diarrhea, gas and bloating, and a slight fever. Some people have no symptoms, but symptoms can last 1 to 3 weeks in healthy people.
  • Cryptosporidiosis: This is an extremely common parasite found in water sources that pass from an infected human or animal. Vomiting, diarrhea, and slight fever can persist for up to two weeks in healthy adults. People with compromised immune systems may need hospitalization.


These are non-natural chemicals such as pesticides and pollutants used by humans. The following pesticide and pollutants are found in these waters:

  • Agriculture: In the United States, this is the number one source of contamination in rivers and streams, the second-biggest in wetlands, and the third in lakes. Each time it rains, fertilizer, animal waste, and pesticides are washed into bodies of water.
  • Used Water: This is water that comes from toilets, sinks, and showers. Think sewage, wastewater, and stormwater runoff. Rural areas that wastewater treatment facilities do not treat can contain pollutants, nitrogen, heavy metals, and phosphorus.
  • Oil: We’re not talking about the big oil spills in headlines. Major spills only account for 10 percent of the oil in waters worldwide. Rural water sources are affected each year by land-based sources such as factories, farms, and cities.
  • Radiation: Radioactive waste involves any pollution emitting radiation generated by nuclear power plants, military weapons production and testing, and research done at hospitals and universities.

The best way to know your water is free from these and other contaminants is to treat it yourself, but should you boil or filter it? Let’s dive into the pros and cons of boiling vs filtering water.

Boiling vs Filtering Water: Pros and Cons

Both methods have pros and cons when it comes to boiling vs filtering water. Let’s talk about what makes each method a good choice as well as the downsides of each.

Pros of Boiling Water

Boiling water in a pot while camping.

When done correctly, boiling water kills 99.999% of viruses, bacteria, and parasites caused by organic contaminants. The CDC recommends bringing water to a full rolling boil for one minute to purify it of germs.

Cons of Boiling Water

Boiling water is incapable of making chemically contaminated water safe. You should never boil cloudy water and expect it to be safe to drink. Cloudy water is a sign of toxic chemicals caused by pollution or erosion. The only way to make cloudy water safe to drink is by filtering it.

Pros of Filtering Water

A camper using a water filter in a river or stream.

Filtered water usually tastes better than boiled water and is faster than boiling water (and doesn’t require fire or heat). It is also the only way to remove toxic chemicals.

Cons of Filtering Water

Water filtration is more expensive than boiling water; not all water filters are the same. Some filters do not filter viruses and bacteria (although most filter parasites).

You need to pay close attention to the manufacturer’s guides and warnings when using water filtration devices to know exactly what you’re filtering. Water filtration devices also have water filters that need to be replaced from time to time to keep working properly.

So Which Is Better and Safer?

The answer is: it depends on various factors.

A high-quality filter that is capable of filtering out viruses, bacteria, and parasites is certainly better and safer than boiling water. But what makes a filtration system high quality and capable of filtering out viruses and bacteria, and how do you identify these filters?

What should you look for in a water filter?

Unfortunately, the water filtration market is unregulated, so a company can make any claims about its product. For your safety, it’s important to be aware of the make-up of the product and what makes a good water filtration system.


Many portable water filters are labeled as microfilters. Microfilters work by removing small amounts of material at a time. They are not intended for large amounts of water at a time.

Portable Water Purifier vs Portable Water Filter

A device marketed as a portable water purifier can remove, kill, or deactivate every type of bacteria, virus, and parasite.

Meanwhile, a device marketed as a portable water filter will typically only filter bacteria and parasites, but it will not viruses. Viruses are too small to be filtered by these devices.

Therefore, you should look for products marketed as water purifiers.

A hiker drinking water from a bottle.

Environmental Protection Agency (EPA) Standard Protocol

EPA standards for water filtration were released in 1987 and have become the standard for identifying how much contamination.

The best way to know how well a water filtration device works is to look for labels mentioning National Sanitation Foundation (NSF) standards.

NSF Standard 42

A product that meets NSF Standard 42 is designed to reduce non-health-related contaminants such as chlorine in water. This standard also covers improving the taste and odor of water.

NSF Standard 53 or 58

A product labeled as meeting NSF standards 53 or 58 indicates it will filter parasites but not remove viruses or parasites.

NSF Standard P231

This protocol requires water to be tested on two different types of water over 11 days (or the life of the filter, whichever ends first). The first type of water is spiked tap water, and the second type is dirty water with plenty of bacteria and viruses designed to represent the worst-case scenario.

For a water filter to be superior to boiling in the boiling vs filter water debate, it must pass this protocol.

NSF Standard P248

This standard is great to see on products intended for backpacking because it meets NSF P231, though it tweaks it slightly to simulate what the military would see on field missions overseas. NSF P248 tests against the worst-case wilderness water.

Testing Laboratories

If the water filter’s manufacturer mentions a testing laboratory in its description or handbook, it should be one of the following. If you see another laboratory listed, then you should be skeptical:

  • NSF (National Sanitation Foundation) in Ann Arbor, Michigan
  • BCS (Biological Consulting Services) in Gainesville, Florida
  • Biovir Laboratories in Benicia, California (now closed)
  • WQA (Water Quality Association) in Lisle, Illinois
  • SGS Corporate Worldwide (now closed)
  • University Laboratories (various locations worldwide)

Contents of the Water Filter

You need to pay attention to the contents of what makes up the water filter, which will help you identify how the product works. Look for the following:

Hollow Fibre Membranes

Hollow fiber membranes block pores and prevent water from passing through when they are full, so you can easily tell when your filter’s cartridge needs replacing. This prevents you from unknowingly drinking unfiltered, diseased water accidentally.

Pore Size

The size of the pores is the most important detail because pores must be smaller than whatever the product intends to filter. A hollow fiber with a pore size of 100 or 200 nanometers can block parasites and bacteria, but viruses are smaller and would not be filtered.

A water filtration product’s pores must be approximately 15 nanometers to prevent viruses from passing through.

Adsorptive Technology

Some water purifiers rely on elements to have chemical reactions with contaminants found in water. As the pattern passes through, contaminants stick to the elements, and then safe water passes through.

This works well for a short time, but over time this becomes ineffective and will cause unsafe water to come through. You also can’t tell when the product has stopped working.

Recommended Water Filters for Camping

We’ve researched numerous water filters designed for camping, and these portable water filters are our favorites.

If you’re RV camping, check out the best water filters for RVs.

Life Saver Jerrycan Water Purifier

The Life Saver water filter system exceeds the NSF P248 and is designed to filter the worst-case, dirtiest water (including viruses). This is the safest portable water filter for backpackers or those drinking from foreign water sources.

LifeStraw Go Water Filter Bottle

The LifeStraw uses hollow fiber membranes and has been tested to filter bacteria, chemicals, and microplastics (but not viruses).

Katadyn Pocket Water Filter

The Katadyn water filter uses 200-nanometer pores to protect you from bacteria, chemicals, and parasites (but not viruses). We like this product because it can filter a whopping 50,000 liters before needing replacing, depending on the water quality.

Boiling Filtered Water or Filtering Boiled Water

You might be wondering if you should just boil filtered water to maximize safety. This is exactly what is recommended in cases where your water filtration system is not trusted to filter viruses.

Should you ever filter boiled water? You could filter cloudy water after it’s boiled, but it makes more sense to filter the cloudy water first and then boil it if you feel it’s necessary.

Boiling vs Filtering Water: What’s the Verdict?

A camper pouring water into a metal camping mug.

So what does it mean when the CDC says, “Boiling water is the surest method to kill disease-causing organisms, including viruses, bacteria, and parasites.”? It simply means that boiling water is the best way to kill contaminants like viruses, bacteria, and parasites.

However, boiling water is incapable of killing man-made environmental pollutants, and that’s where water filters are superior.

As for boiling water vs filtering water, which is better and safer? Neither is necessarily better or safer than the other. They both serve their purpose and can work together to create the purest, safest water for consumption.

We recommend carrying a water purifier with you in case you encounter cloudy, polluted water. Check out other camping gear we recommend bringing with you on your next camping trip.