Water filter pitchers are an affordable and easy way to remove many different contaminants from water. Removing bacteria (and viruses) can be a little more difficult but there are some brads of filter pitchers that can.
Water filter pitchers certified to NSF standards 244 or P231 can remove bacteria from water. Water filter pitchers with absolute pore sizes of less than or equal to 0.3 microns will offer moderate effectiveness against bacteria. Filter pitchers with UV purification or filters that contain silver can, respectively, help disinfect water or reduce biofilm buildup.
In this post, we’ll explain everything about waterborne bacteria including which water filter pitchers can actually remove them from drinking water. We will detail the negative effects of bacteria, how certain water filter pitchers can remove bacteria, and how bacteria get into our water supply.
Overall, we highly recommend these two water filter pitchers as they are certified to NSF standards to remove bacteria (NSF-244 or -P231), plus they both have long filter-lives:
What are Bacteria?
Bacteria are single-celled microscopic organisms that can freely exist practically anywhere around the world. There are many different types of bacteria and can be found in the soil, water, on the rocks, or even in the human body.
Most bacteria are harmless to humans. However, some bacteria are pathogenic, which means that they can cause diseases.
Waterborne bacteria are quite common, and some can cause various health conditions if ingested through drinking water or breathed into the lungs.
Different types of waterborne bacteria
Some of the waterborne bacteria with potential harm to human health, include:
- Pseudomonas: Pseudomonas aeruginosa are bacterium that can cause various infections like otitis, conjunctivitis, and folliculitis.
- Mycobacteria: Nontuberculous mycobacteria are environmental organisms found in municipal and natural water sources. They can cause respiratory infections, especially in people with underlying lung disease or depressed immune systems.
- Klebslella: Bacteria of the Klebslella genus can cause various diseases in humans and are commonly found in surface water, drinking water, soil, and sewage. The waterborne Klebslella pneumoniae species is often associated with various health conditions including pneumonia, meningitis. urinary tract infections, and soft tissue infections.
- Salmonella: Salmonellae are gram-negative, rod-shaped bacteria. These pathogens, which can survive for several weeks in water and soil in favorable environments, are primarily introduced into natural waters by municipal sewage, agricultural waste, and stormwater runoff. It causes typhoid when ingested.
- Shigella: Shigella is the infectious substance of shigellosis bacteria, also known as bacillary dysentery, which is contagious by direct contact with an infected person, contaminated food, or drinking water.
- Escherichia: When ingested in water, the gram-negative bacteria Escherichia can cause gastroenteritis in children, diarrhea, and hemorrhagic colitis. E-coli is one of the most well-known species of Escherichia.
- Francisella: Francisella tularensis, the type species of the genus, has four subspecies and is a highly contagious bacteria that causes sickness such as tularemia in humans when consumed in water.
- Legionella spp.: It is a genus of Gram-negative bacteria and the sole member of the Legionellaceae family. Legionnaires’ disease, a severe form of pneumonia that affects people worldwide, is caused by Legionella pneumophila. They are found naturally in freshwater environments but can grow and spread in home faucets and showerheads.
- Burkholderia cepacia: A class of bacteria known as Burkholderia cepacia can be found in soil and water and is frequently resistant to standard medications.
Negative health effects of bacteria
Although some bacteria can be beneficial to the human gut, many bacteria can be detrimental to human health.
According to the Centers for Diseases Control and Prevention (CDC), most healthy people exposed to bacteria-contaminated water may not get sick.
However, the following groups of people are at increased risk:
- The elderly.
- Contact lens users (mainly due increased physical contact with the lens/eye from touching)
- People whose immune systems have been compromised such as from cancer, organ transplantation, or HIV
- Those who suffer from underlying conditions like diabetes, renal failure, or liver failure
- Children younger than six months.
- Smokers, and ex-smokers.
- Those suffering from a long-term lung condition such as chronic obstructive pulmonary disease (COPD).
The following are some of the effects of drinking water that has bacteria.
According to the CDC, drinking bacteria-contaminated water may lead to;
- Stomach illnesses, i.e., vomiting and diarrhea.
- Death in extreme cases
- Fever
- Nausea
- Headaches
- Fatigue
- Cramps
- Ingesting harmful bacteria can lead to dangerous infections such as cholera (caused by vibrio cholerae) and typhoid (caused by Salmonella typhi).
- According to research, it can also cause respiratory, eye, skin, or ear issues.
How water filter pitchers remove bacteria
Many water filter pitchers can reduce a suite of contaminants from water, but not every water filter pitcher can get rid of bacteria.
Here’s what to look out for:
Pore size
Filters with an absolute pore size of less than or equal to 0.3 microns offer moderate effectiveness at removing harmful bacteria and cysts from water.
The smaller the pore size in the filter, the more effective they will be at mechanically stopping harmful microorganisms such as bacteria or cysts from getting into your drinking water.
Testing – Certifications
Filter pitchers that are certified to National Sanitation Foundation (NSF) / American National Standards Institute (ANSI) standards 244 or P231 mean they have been independently tested to remove microorganisms such as bacteria, cysts, and viruses.
While it is not compulsory for a water filter to be certified to NSF standards, they certainly make it easier to determine if the product does what the company claims it can.
There are important differences between these NSF certifications.
NSF-244
The NSF-244 standard is designed to test filters for the supplemental microbial control of specific organisms that…
“May occasionally be present in drinking water”
but
“Should not be used with water that is microbiologically unsafe or of unknown quality”
NSF-P231
In comparison, the NSF-P231 standard is for filters that could be used for…
“Waters of unknown microbiological quality, but are presumed to be potable”
Basically, a water filter pitcher carrying either these NSF certifications (NSF 244 or P231) will be effective at removing bacteria when used to filter tap water that has been treated to public water system standards.
However, a pitcher with the NSF-244 certification may not necessarily remove the same level of microbial contaminants when the microbiological water quality is unknown, such as during a boil water advisory or from a private (domestic) well.
Note: Some water filter pitcher brands will state they are NSF certified, but this does not necessarily mean they are tested to remove microbiological contaminants.
For example, it is quite common for filter pitcher brands to carry NSF certifications 42 and/or 53, which relate to the removal of aesthetic impurities and contaminants that can have negative health effects, respectively.
So, it’s important to know your NSF numbers when you’re looking for a filter pitcher to remove bacteria and other microbes.
Silver
Silver technology is sometimes used in water filter pitchers to inhibit bacterial growth within the filter media itself.
When silver comes in contact with moisture, silver ions and/or silver nanoparticles are released that prevent bacterial DNA replication, which will eventually kill them. This not only helps control the growth of biofilms (large bacterial populations) in the pitcher or dispenser, but it can also make the filter last longer.

Water Purification Guide has more information on how silver can be used to disinfect your water available here.
Ultraviolet light
Ultraviolet light is a powerful way to kill bacteria from water. It’s important that they are combined with a pre-sediment filter of some sort, which allows the UV light to penetrate the water completely. Otherwise, a lot of the UV light gets dispersed, and the UV germicidal irradiation is incomplete.
There are 3 types of UltraViolet (UV) light:
- UVA
- UVB
- UVC
UVC-light is the most harmful to bacteria and viruses in water. It will even kill viruses at the DNA level.
Although voluntary, reputable companies are typically certified to NSF/ANSI 55 standards (UltraViolet Microbial Water Treatment Systems) to prove they actually kill bacteria and viruses.
Ultraviolet Light systems should be labeled Class A or Class B systems.
- Class A systems can inactivate pathogenic organisms using a UV dose at the energy wavelength of 254 nm (40 mJ/cm²).
- Class B systems can inactivate non-pathogenic organisms using a lower UV dose at 16 mJ/cm².
5 water filter pitchers that remove bacteria
Not all water filter pitchers can remove bacteria from your drinking water hence why this list is short.
1. Clearly Filtered water filter pitcher
The Clearly Filtered Water Pitcher is NSF-244 certified to remove 99.99% of bacteria, including:
- E. Coli
- Klebslella spp.
Clearly Filtered pitchers are also capable of removing 99.99% of harmful microbiological contaminants in water including Giardia, Cryptosporidium, Algae, Amoeba, Cysts and 99.9999% of viruses (including MS2 Phage and Rotavirus).
It is also NSF certified to standards 42, 53, 401, and 473 allowing it to remove up to 99.9% of 365+ hazardous and dangerous tap water contaminants.
Among others, Clearly Filtered pitchers remove:
CONTAMINANT
Fluoride
PFAS (9 types)
Microplastics
Lead
Arsenic
Chlorine
Viruses
BPA
Glyphosate
VOCs
% REMOVED
>99.5%
>95.0%
>99.9%
>99.3%
98.3%
>99.5%
99.9999%
>99.9%
>99.9%
>97.9%
This company has thought of everything. The pitcher even has a “water dam” that is built inside the top reservoir that stops any unfiltered water (including microbiological contaminants) from spilling over into the filtered water. This extra layer of protection is certainly something we have not seen from other brands.
Each filter will last around 100 gallons (~455 L) before needing to be replaced.
Pros;
- BPA/BPS-free
- Built in water dam
- Made from medical-grade Tritan materials
- Built in the USA
- Limited lifetime warranty
Cons:
- No filter timer indicator
2. Epic Nano water filter pitcher
The USA-made Epic Nano water filter Pitcher carries the NSF-P231 certification and can eliminate up to 99.9999% of bacteria, including:
- Pseudomonas aeruginosa
- E. Coli
- Klebslella pneumoniae
It can also remove 99.999% of harmful germs such as Giardia (protazoan flagellates), Cryptosporidium (parasites), and 99.95% of MS2 Phage (virus).
Not only is this water filter pitcher effective at removing bacteria, parasites and viruses, it is certified to NSF/ANSI standards 42, 53, 401, and P473 and can remove 99.999% of harmful tap water contaminants. Some of these include:
CONTAMINANT
Fluoride
PFAS (2 types)
Microplastics
Lead
Arsenic
Chlorine
Virus
BPA
Glyphosate
VOCs
% REMOVED
68.0%
>99.6%
99.25%
>99.4%
95.0%
96.8%
99.95%
>99.0%
>99.9%
>93.6%
To eliminate microorganisms from drinking water, the Epic nano water filter pitcher uses a sub-micron (<1 micron) nanofiber technology in their filter. The filter mechanically removes bacteria, allowing only clean water to pass through.
It employs a combination of nanofiber technology, ion exchange, activated carbon to remove harmful water contaminants.
The Nano Pitcher also includes an embedded LED timer that counts down from 90 days and alerts you when it’s time to change the filter. Each filter provides an impressive ~150 gallons (568 L) of clean, safe drinking water before needing to be replaced.
Pros:
- BPA-free
- USA-made filters
- It features a lifetime warranty – 100% money back.
- Digital filter timer indicator
Cons:
- It is not to be filled with hot water or used with salt water.
3. Lifestraw Home water filter pitcher
The LifeStraw Home Water Filter Pitcher is certified to NSF standards P231 for the removal of 99.999999% bacteria such as E. coli, and 99.999% parasites such as Giardia and Cryptosporidium.
It is also certified to NSF standards 42, 53, and 401. The combination of activated carbon, ion exchange, and microfiltration (down to 0.2 microns) makes the LifeStraw Home pitcher effective at reducing germs, PFAS, microplastics, chlorine, herbicides, heavy metals, pesticides, dirt, sand, and cloudiness while leaving behind healthy minerals like magnesium and potassium in the filtered water.
There are two filters:
- The membrane microfilter lasts approximately 264 gallons (1,000 L), which equates to a filter change about once every year.
- The activated carbon + ion exchange filter needs replacing approximately every 40 gallons (150 L), which is about 2 months of normal use.
Pros:
- Membrane microfiltration (0.2 microns)
- Meets NSF-P231 standards for removal of microbiological contaminants.
- Borosilicate glass pitcher
Cons:
- No filter timer indicator
4. Clear2O Advanced Gravity water filter pitcher
Clear2O advanced gravity water filter pitcher can filter contaminants to sub-micron level (less than 1 micron) and is likely capable of reducing some microbiological contaminants.
The company claims to reduce Cryptosporidium cysts, which are approximately 4.2 – 5.4 microns in diameter, and Giardia cysts (~8 – 19 microns in size). While these are not bacteria, the sub-micron filter should be more than capable of achieving this.
The pitcher is certified to NSF 42 and 53 standards. This means it can get rid of the bad taste, color, and smell in your drinking water, and will reduce harmful contaminants such as lead, sediment, rust, among others. However, they are not certified to NSF-244 or -P231 standards, which relate to the removal of bacteria and other microbiological contaminants.
Pros:
- BPA-free
- Sub-micron filter
Cons:
- Not certified to NSF-244 or P231 standards for removing bacteria or other microbiological contaminants.
5. GOSOIT UV water filter pitcher
The GOSOIT water filter pitcher is made in China and claims to remove 99.99% of bacteria, viruses, spores, and E. coli. This sounds great, but the pitcher is not certified to NSF standards to remove microorganisms from water. In fact, GOSOIT pitchers do not have any certifications showing they can do this.
While it is probable that the ultrafiltraiton membrane would remove a high level of microbiological contaminants, we have no way of knowing that this is true. So, it’s up to you whether or not will take the risk or not.
It also uses UltraViolet light to kill bacteria and other microbes in water. However, they do not state what type of UV light is used or at what energy wavelength. Water treatment systems that use UV light for germicidal irradiation can be tested to NSF-55 standards. GOSOIT have not chosen to do this – so again, we will just have to take their word for it.
I would love to give this UV water filter pitcher a better review as it certainly looks cool and probably can kill certain waterborne microorganisms. However, I would personally go for a brand that has proven their technology through accredited avenues. This is why it’s at the bottom of our list.
How do bacteria get into our water supply?
There are many different ways in which bacteria can enter our water supply, such as;
- Bacteria growing in water pipes, faucets, shower heads etc.
- Soil particles harboring bacteria that travel in the water.
- Private (domestic) wells.
- A pipe leak brought on by their aging or bursting.
- Flooding causing treated water contamination.
- Human and animal wastes.
- Defective septic systems.
- Sanitary sewer pipes with leaks.
- Sewage system treatment that was installed incorrectly.
- Untreated surface water contaminating treated municipal water.
What water filters remove bacteria and viruses?
Bacteria
The effectiveness of any water filter at removing or reducing the bacteria in water depends on the filtration technology. The methods that are recommended by the CDC to have a VERY HIGH effectiveness at removing harmful bacteria are:
- Ultrafiltration
- Nanofiltration
- Distillation
- Ultraviolet (UV) systems (that include pre-filtration)
- Reverse osmosis
Filtration technologies that should be avoided include:
- Microfiltration – MODERATE effectiveness at removing bacteria
- Water softeners – NOT effective at removing bacteria
Viruses
Removing viruses can be more difficult and according to the CDC, different filtration technologies have varied effectiveness, including:
- Microfiltration – NOT effective
- Water softeners – NOT effective
- Ultrafiltration – MODERATELY effective
- Nanofiltration – VERY effective
- Reverse osmosis – VERY effective
- Distillation – VERY effective
- Ultraviolet (UV) systems (that includes pre-filtration) – HIGH effectiveness
Do Brita filters remove bacteria?
Brita filters are not designed to purify water and should not be used with water that is microbiologically unsafe or if the water quality is unknown, such as during a boil water advisory or from private wells.
Brita filters are certified to NSF standards 42, 53, and some Brita products are also certified to NSF standard 401. However, these certifications do not cover the removal or reduction of microbiological contaminants including bacteria, viruses, or parasites.
The Best Water Filter Pitchers We’ve Reviewed
Clearly Filtered | Affinity Filtration Technology
We really love the ClearlyFiltered pitcher as it removes 99.9% of 365+ contaminants from tap water including fluoride, microplastics, and even amoeba! It produces 100 gallons of water over the filter’s 4-month lifespan. You can buy them here at clearlyfiltered.com
Epic Water | Nano
These nano filtration pitchers are an absolutely amazing! They remove up to 99.999% of all tap water contaminants including microplastics, bacteria, giardia, cryptosporidium, and viruses. It’ll produce a massive 150 gallons of water and the filters last 3-4 months! Check them out at EpicWater right now.
