a man pouring water from filter tap

Water Filter vs Reverse Osmosis (What’s the Difference?)

Want to know the difference between reverse osmosis and water filters?

You’re in the right place. Read on and find out. 

How is reverse osmosis different from filtration?

Water filters don’t eliminate dissolved chemicals as they can physically block dirt and sediment particles about a millimeter in size from water. 

On the other hand, reverse osmosis uses a delicate membrane to filter molecule-sized sediments eliminating dissolved chemicals and salts that a standard filter cannot.

In reverse osmosis, only pure water passes through the membrane while the feed water passes across the membranes to avoid clogging. With regular filters, all the water flows through the filter with standard filters, allowing particles to gather in it or its surface, eventually blocking it.

What is a water filter?

This device utilizes one or more filtration methodologies to minimize the number of pollutants in water. Although water filters come in various types and sizes, they aim to eliminate unwanted impurities like bacteria, sediments, hardness, foul odor, and taste from water to improve its quality.

What contaminants do carbon water filters effectively remove?

Carbon water filters are effective in removing things like:

  • Some pesticides, herbicides, and other organic contaminants
  • Disinfectants such as chlorine
  • Volatile Organic Compounds (VOCs) and other solvents include fuel oil, polychlorinated biphenyls, dioxins, and radioactive material.
  • Unpleasant tastes and odors
  • Dirt
  • Heavy metals
  • Parasites like giardia and cryptosporidium
  • Rust 
  • Sediment
  • Arsenic


Capacity to remove harmful substances

Carbon water filters can remove contaminants like arsenic, heavy metals, dirt, etc., from the water .making it safe for consumption.

Improves taste and smell of water

Carbon filters eliminate chlorine, sediments, and other organic chemicals to give water a  fresh taste and odor.

Low cost and maintenance

Carbon filters are among the least priced filters and require little maintenance.

Retain healthy nutrients

Carbon filters remove harmful substances from your water without ridding it of healthy minerals.


Inability to remove specific pollutants

Some carbon filters may not have the ability to remove certain chemicals like heavy metals, nitrates, sodium, and other harmful microorganisms.

Need for regular replacement

For carbon water filters to function effectively, they need periodic replacement to avoid contaminating water even more.

Slow filtration

Carbon filters take some time to produce clean water. The water requires a long contact time with the filter media. 

What is reverse osmosis?

It is a technique of eliminating dissolved inorganic particles like magnesium and calcium ions from water by forcing them through a semipermeable membrane under pressure so that the water passes through, leaving most of the pollutants behind. 

How does reverse osmosis water filtration work?

The reverse osmosis system removes sediment and chlorine by passing the water through a carbon filter first. Then, forcing the water through a delicate semipermeable membrane designed to eliminate all impurities. Lastly, the water passes through a postfilter to polish the water for consumption removing 97% of all water impurities.

What contaminants can reverse osmosis systems reduce?

These are the contaminants removed effectively through reverse osmosis:

  • Bacterias, including salmonella, E. coli, and Shigella, effectively remove pollutants from water to make it safe for consumption. 


It’s highly effective in removing contaminants.

Reverse osmosis reduces most of the harmful dissolved water contaminants, including fluoride, arsenic, sodium, mercury, and lead, among many others.

It’s convenient

Reverse osmosis provides clean water on demand as it connects directly to your faucet.

Better taste and odor

The process removes chlorine added to water hence improving its taste and smell.


Removes healthy minerals

Ro is too compelling and removes everything, including the good stuff like healthy minerals.

Produces water with a flat taste 

Since it removes all minerals, this process results in water with a bland taste.

Creates water waste

While it’s effective in producing clean water, it wastes water in the process. Water waste is necessary for this process, or clogging of the membrane will result in damaging it.


Aim to eliminate reverse osmosis considered filtered water?

Yes. Reverse osmosis is a kind of filtration that uses a semipermeable membrane to remove unwanted contaminants like chlorine, bacteria, sediments, etc., from water. 

Is reverse osmosis the best way to purify water?

Reverse osmosis is an effective water purification method considered to be among the best ways to remove up to 99% of dissolved contaminants.

What is not removed by reverse osmosis?

Some contaminants have molecules smaller than water that reverse osmosis can’t remove. These include:

  • Dissolved gases like hydrogen sulfide
  • Herbicides
  • Pesticides
  • Agricultural treatment products like Fungicides 
  • Certain organic compounds

What is better, water filter or reverse osmosis?

It depends on an individual’s preference. Reverse osmosis is effective in removing a more comprehensive range of contaminants. However, it removes even the useful stuff giving the water a flat taste. Water filters retain healthy minerals.

Will Reverse Osmosis remove bacteria?

Yes. Reverse osmosis is effective in removing most bacteria. It uses a fine membrane with tiny holes which filter delicate bacteria and blocks them from passing through, then flushes them down the drain.

How long should a reverse osmosis system last?

Reverse osmosis systems last for an average of between 10-15 years. However, the reverse osmosis membrane and filters need regular replacing for them to work effectively.  


So, which method is suitable for you?

It depends on your preference. 

Evaluate the benefits of both and make your choice

Joshua Perkins

Joshua spent ten years as a water systems technician in California before settling down with his wife and two young children in Nashville in 2018. Through all of his experience, he learned the benefits and shortfalls of so many different types of water filtration systems, from pitchers to whole-house installations. He started Water Filter Authority in 2019 to empower other families to make the right decision for their long-term health and wellness.