Whole House vs Under Sink Water Filters: What’s Better?

Author: Jason Hollow - Published: 2021/09/24 - Updated: 2022/11/22

Disclaimer: This page may contain affiliate links. If you buy a product or service through an affiliate link, we may earn a commission but at no additional cost to you. You can view our full affiliate disclosure here.

If you find yourself pinching your nose every time you hold a glass of water filled at the kitchen faucet to your mouth, then you’re probably ready for a water filtration system. Besides improving the taste and smell of drinking water, a home water filter works tirelessly to keep your family safe from hundreds of impurities.

Thanks to advancements in technology, you have tons of water filtration gadgets and systems to choose from – such as under sink and whole house water filters.

Both treat water on demand, and the modern design of these systems has thought of it all. But which type is better? Unfortunately, there’s no simple answer to this conundrum. The best choice for your house is the one that fits your budget, your unique water chemistry and what you expect from it.

Not very helpful? Well, today we compare under sink water filters with whole house water filters in detailed. Hopefully, by the end of the article, you’ll be able to choose with confidence.

So, here is our guide on whole house vs under sink water filter!


  • Have your water tested for minerals and contaminants. You can then choose which is the better option depending on your water quality and needs.
  • If the main problem is substandard drinking water quality, the better option will be to go for an under sink water filter. This type of system doesn’t need much space and is easy to install and maintain.
  • If your problem concerns limescale, clogged plumbing and appliances, stained clothes, unhealthy skin and hair, or similar issues, then you won’t go wrong choosing a whole house filter. This will address the filtered water requirement for your entire household. However, POE systems are more expensive and more complex to install.

The Difference Between Whole House and Under Sink Water Filters

Under Sink vs Whole House Water Filter Thumbnail

Residential water filtration systems are known to be easy-to-use and efficient at bringing a noticeable and measurable change in the chemistry of your water supply. However, this is where the similarity between the various types of water filters ends. Allow us to explain how!

A whole house water filter, also called a point-of-entry filter, is installed right where water enters your house. Consequently, it not only protects your family from water-borne diseases but also increases the life of your plumbing and water-based appliances by removing contaminants like sediment.

In contrast, an under sink water filter treats water at the point of use, aka your kitchen sink. They’re much smaller, but their performance should not be underestimated.

Most good-quality under sink filters are designed to improve the aesthetics of your water and remove a wide range of harmful contaminants. Hence, these compact units ensure you receive filtered water for cooking and drinking around the clock.

The Benefits of a Whole House Water Filter

When you opt for a whole house water filter, you can expect the following benefits (and many more!).

  • To start, whole house water filters are often equipped with multi-stage filtration to tackle many contaminant types – whether big, small or microscopic. The best ones can remove sediment at the sub-micron level, filter out harmful chemicals like pesticides and PFAS, and finally inactivate all bacteria and viruses. So by the time the water reaches your taps and faucets, you can be sure it’s pure and as refreshing as spring water.
  • Perhaps the biggest reason whole house water filters have an edge over all other types of home filter systems is that they protect your plumbing and appliances from choking due to sediment and rust etc. This is because water high in dirt, iron and scale causes buildup in pipelines and wreaks havoc on water heaters, dishwashers and washing machines.
  • Eventually, you notice an increase in water pressure due to better plumbing and a decline in repair costs of your major home appliances.
  • Another significant benefit is that many people will notice a substantial improvement in their skin and hair health. Why is that so? Unwanted chemicals and minerals in tap water can exacerbate skin dryness and flare up symptoms for people with eczema and psoriasis. It also damages the hair shaft, making it brittle and unruly. As you shower with filtered water, your skin and hair will forever be grateful to you.
  • Have you noticed that your clothes are not as bright after washing or have brownish-red stains on them? Naturally, dirty, contaminated water is the culprit. As your washer starts to use filtered water, you will notice cleaner and brighter clothes. Similarly, your dishes will also have fewer smudges and appear shinier.

The Benefits of an Under Sink Water Filtration System

For comparison, here are a few advantages of under sink water filters.

  • They are readily available and relatively inexpensive as compared to serious whole house water filters. Even with a limited budget, you can purchase a good quality under sink filtration system at a nominal price.
  • Due to the non-complex design, most under sink systems are fuss-free and easy to maintain. With timely filter replacements and regular cleaning, a good quality unit will last you for years on end.
  • These systems require minimal installation and can easily be set up at rentals. Neither do you need to pay exorbitant installation fees nor make permanent changes to your plumbing.
  • They can fit in almost all kitchens and be away from plain sight, unlike whole house water filters that require dedicated space near the water meter.
  • What’s more, the filtration performance of an under sink water filter system can be remarkable. Some of these nifty units employ multi-layer filtration and thoroughly clean your water without compromising water pressure.

Find Out What’s in Your Water

Choosing an under sink water filter over a whole house system or vice versa isn’t just a matter of picking the nicest one within your budget. It’s all about defining what you want from your filter and ensuring it meets your needs, so your life is easier and far safer.

So, what exactly do you need? The answer lies in the quality of your water supply.

For instance, if your only complaint with tap water is poor chlorine smell and taste, an under sink system is your best bet. It’ll provide filtered water right at your kitchen faucet which is all you need.[1]

On the other hand, a whole house filtration system is best if you are tired of:

  • Poor skin and hair health
  • Dingy and stained clothes
  • Cloudy glassware
  • Limescale deposits on kettles and water heaters
  • Buildup in plumbing
  • Corroded pipes

woman in testing laboratory holding dirty water glass

How to Test Your Water?

Apart from these obvious signs, some nasty contaminants are too clever to leave obvious marks and will continue to attack your family silently. Here is how you can test your water supply for such contaminants.

  1. Laboratory testing: The most reliable way to test your water is to send a sample to a certified laboratory. It will highlight the level of each contaminant tested, making it easy for you to access the best mode of filtration required.
  2. DIY water test kits: Easily available and inexpensive, water test kits quickly show the primary contaminants in your water supply.
  3. Consumer Confidence Report: Your municipal board has already done the job for you. Just find your local water report on epa.gov and use the results to figure out the best way of treatment.

Whole House vs Under Sink Water Filter OR Using Both?

At the risk of sounding contradictory, the best advice we have is to combine an under sink water filter with a whole house unit to get a dual line of defense against dirty and contaminated water.

This brings us to the million-dollar question: Isn’t a whole house filter as effective as a drinking water filter? Yes and no!

You see, water filtration is evidently more effective when water spends more time in contact with the filter media. Of course, increasing contact time in a whole house system would result in a noticeable drop in water pressure around the house. Whereas in a compact system that only treats less water at a time, you can expect better purification.

So, let’s say your water is high in sediment, chemicals, heavy metals, dissolved organic compounds; you can install a sediment whole house water filter to protect your plumbing system in conjunction with an under sink water filter to fish 99.9% of contaminants out of your drinking water.


In conclusion, the difference between an under sink water filter and a whole house system is that the former is for drinking water purposes only, while the latter also protects your plumbing and appliances from damage.

This is also the main benefit of whole house water filters: the fact that they purify the entire water supply which also helps your water heater, dishwasher and washing machine etc.

In contrast, under sink systems are better suited at removing harmful contaminants from water intended for direct consumption.

Which to choose? It’s best to start by testing your water quality.

Ideally you use a combination of both whole house water filtration and under sink water treatment.

Further Reading


Meet Jason Hollow

Jason Hollow Jason is the founder of Water Masterz and head of content creation. After six years in the industry, he has tremendous knowledge and first-hand experience on all things related to water treatment.

His credo: Not a single American should have to drink unhealthy water at home.

Leave a Reply

Your email address will not be published. Required fields are marked *

eighteen − 1 =