Under Sink vs Whole House Water Filter – Which to Choose?

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Is the thought of drinking contaminated water keeping you up at night? Or bottled water creating a dent in your pocket? Perhaps, the Flint crisis shook you up.

The chances are good that you have stumbled upon the numerous types of water filtration systems. But which one is for you? No short answer for that one!

It ultimately depends on your lifestyle, water quality, water usage, budget, and what you expect out of it. In this guide, we’ll go through two of our favorite systems: Whole house and under sink water filters.

Stay with us as we evaluate the major differences between the two types and help you select one for your home. Ready?

Key Takeaways

  • Choose based on your filtration needs. Tip: Have your water tested.
  • If your main concern is poor drinking water quality, an under sink water filter is probably the better choice. They are easy to install and maintain, and don’t need a lot of space to set up.
  • If you are constantly dealing with clogged appliances and plumbing, limescale, unhealthy hair and skin, stained clothes, and poor lathering of cleaning products, then a whole house filter should be your choice. They provide filtered water throughout the entire home, but are more expensive and difficult to install.

Whole House vs Under Sink Water Filter: The Difference

As the name suggests, a whole house water filter is a point-of-entry system that filters every drop of water that enters your home. Besides improving the taste and quality of drinking water, the unit protects your plumbing and water-based appliances from damage due to heavy metals, sediment, and dirt.

Whole house water filters offer you complete peace of mind that water around your house is filtered.

On the other hand, an under sink water filter is a point-of-use system that ensures a continuous supply of filtered water for drinking and cooking.

Most under sink systems also do a spectacular job at improving the aesthetics of your water. You can finally have pure water; and allow us to tell you, it tastes incredible!

What Are the Benefits of a Whole House Water Filtration System?

Here are a few features of whole house water filtration systems – and how we benefit from them.

  • Most whole house filtration units feature multiple state-of-the-art filter layers. When your water passes through a sophisticated multi-stage system, it is free from sediments, chemicals like chlorine, possibly iron and other heavy metals, volatile organic compounds, and maybe even pathogens like bacteria if there is a UV treatment stage. As a result, your water tastes and smells better, plus your family is shielded from hundreds of unwanted impurities.
  • Water high in sediment and minerals forms hard build-up inside pipes, washing machines, dishwashers, and water heater lines. Similarly, iron can wreak havoc on your pipes, breaking them down. By removing these and other impurities, whole house water filters safeguard plumbing and appliances, elongating their life. You will also notice a considerable decrease in repair costs over time.
  • Not only that, chemicals like chlorine exacerbate skin conditions like eczema and psoriasis. You can now have better showers and baths without unnecessary chemicals touching your skin.
  • At the same time, contaminated water makes your hair dry and brittle. Hence, a whole house water filter promotes better skin and hair health.
  • Since your washing machine also receives clean water free from sediment and iron, your clothes come out brighter and free of reddish-brown stains.
  • On top of that, the limescale deposits on your electric kettle and smudges on glassware will disappear or be less obvious.

What Are the Benefits of an Under Sink Filter?

Under Sink Water Filter

Here is why we love under sink water filters.

  • Under sink filters are inexpensive, easy to install, and even easier to maintain. Most systems last for up to ten years on average and require only minimal maintenance.
  • Compared to whole house filters, they don’t need a lot of space to set up either. They fit snugly inside the kitchen cabinet, out of plain sight.
  • Moreover, they don’t require permanent changes to plumbing, making them ideal for rentals. All you need to do is connect the filter to the cold water line running under the sink.
  • Under sink reverse osmosis water filter systems effectively remove sediment, chlorine, heavy metals, salts, chemicals, microorganisms, and more. Besides improving taste and smell, your water will be more than safe to drink and cook with. On the other hand, whole house RO systems are generally not preferred as they waste a lot of water.

What’s in Your Water?

Whole house or under sink, it’s evident that both types of water filtration systems host numerous benefits. So, the answer for whole house vs under sink water filter lies at your end, or shall we say, in your water.

If your only concern is poor tasting water, an under sink filtration system can take care of it quickly. Some high-quality under sink water filters can also remove stubborn contaminants like chromium 6 and PFAS.

In contrast, a whole house filter should be your choice if you are constantly dealing with clogged appliances and plumbing, limescale, unhealthy hair and skin, stained clothes, and poor lather of cleaning products.

With that said, you must know what’s actually in your water. Most contaminants can go unnoticed for years because they are microscopic; therefore, a test is always essential.

Here’s how you can test your home water:

  • The safest and most reliable method is to send a water sample to a certified laboratory. The results will highlight the level of each contaminant in your water.
  • Similarly, you may use an at-home water test kit.
  • You can also request a water analysis report from your local water utility. However, the results are not always accurate since your water quality is also greatly affected by the distribution channel and plumbing in your house.

Water Testing Report

Combining the Two for a More Complete Filtration

Combining a whole house water filter with an under sink system will give you the best of both worlds. But isn’t a whole house filter as efficient as a drinking water filter?

Guess what? The longer the water stays in contact with the filter media, the more rigorous the filtration is. Since whole house systems tackle a lot of water at one time, slowing down the filtration process would result in a severe loss of water pressure around the house.

So let’s say if your water is highly contaminated, combining an RO system and a multi-stage whole house water filter will provide you with the utmost defense against all contaminants.

If finding a filtration system seems overwhelming due to hundreds of options, here’s a simple trick to weed out the ones that aren’t worth it. According to the Centers for Disease Control and Prevention (CDC), look for NSF marks on products. NSF is an independent research organization that tests multiple products and certifies only those that comply with public health standards.

To sum up, begin by testing your water and then look for the best filtration solution accordingly.

If you have any questions about whole house vs under sink water filter please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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