Whole House Water Filter vs Under Sink Filter: Which is the Best Option for Your Home?

whole house filter vs under sink featured photo

Clean and safe drinking water is important to keep your family healthy—and so is choosing the right filtration system for your home. You want to make sure that it’s reliable, safe, and efficient, so considering the needs of your household should be your top priority.

Whole-house filters clean your water at the source, while under-sink water filters purify water and send it to a designated fixture. Both filters are effective at eliminating pollutants and contaminants from water. The main difference is where they are installed.

That said, it’s not a one-size-fits-all situation. These two filters vary in size and capacity, and one may be more efficient than the other.

In this post, we’ll compare how whole-house and under-sink water filters work. We’ll also go over their differences in terms of the water quality each produces, cost, and pros and cons.

What Is a Whole House Water Filter?

What Is a Whole House Water Filter

A whole-house water filter is a water purifying system that uses a set of filters to treat water. The reason it’s called a whole-house water filter is that it’s installed on the main water line, which is the point of entry of water into your home.

This means that it can provide clean and filtered water that runs from each tap in your house, from your showerhead to your sink to even your dishwasher. It’s a type of point-of-entry (POE) water filter that serves as a tap water portal, allowing only clean, filtered water to pass to your fixtures and appliances.

One of the best things about such a type of filtration system is that it eliminates any contaminants right from the source. Water passes through a complex multistage system when a whole-house water filtration system is in use, clearing it of sediments, water hardness, and volatile organic compounds (VOCs).

If the unit has a UV treatment, it can even kill pathogens like bacteria. Plus, it helps extend the lifespan of your appliances and pipelines because it lessens limescale buildup. 

Also, if you choose a whole-house filter, you’re keeping chlorine from coming into contact with your skin and hair. This chemical is harsh and can make your hair brittle and aggravate skin conditions.


  • Treats water from the source
  • Supplies clean, fresh water throughout the house
  • Eliminates a range of impurities and contaminants in the water
  • Protects your pipeworks and appliances since it removes hardness from water


  • Can be expensive to run
  • Requires plumbing upgrades and professional upkeep

What Is an Under-Sink Water Filter?

What Is an Under-Sink Water Filter

Unlike whole-house water filters, under-sink water filters are a point-of-use (POU) type of filter. They are, as the name implies, installed underneath a sink and supply water through a pipeline to a designed faucet.

If you want safe drinking water from your kitchen tap, this would be a more affordable option. It’s inexpensive and offers easy installation and maintenance. Under-sink water filters also take up less space to install than whole-house filters. You can easily tuck them into your kitchen cabinet.

What’s more? You don’t need to modify your plumbing. It’s a plug-and-play situation here.

Under-sink water filters eliminate chlorine, heavy metals, sediments, bacteria, and chemicals from water. They also improve the taste and smell of tap water because they are designed to produce clean and safe drinking water.

The downside is that it does not provide treated water throughout your home, which is something that whole-house treatments excel at. This also exposes the rest of your pipes and water-based appliances to limescale buildup, which can be expensive to repair.


  • Saves space and can be tucked inside the cupboard
  • Easy installation and maintenance
  • Doesn’t require plumbing upgrades
  • Affordable option


  • Doesn’t supply water throughout the house
  • Needs routine maintenance
  • Restricts flow rate

Whole House Water Filter vs Under Sink Filter: What’s the Difference?

The most obvious difference between a whole-house water filter and an under-sink filter is where they’re installed.

Because whole-house water filters are installed at the point where the water enters your home, they can supply filtered water to use for showers, laundry, and dishwashing. They not only improve the taste and overall quality of drinking water, but it also protects your pipework and appliances from limescale buildup and dirt.

Under-sink filters, on the other hand, are installed on a dedicated tap, which is your kitchen sink. Such filters are mainly for filtering water for consumption. This also means that it won’t protect the rest of your pipelines since it only sends treated water to a single faucet.

Now, let’s compare the whole-house water filter and under-sink filter system in terms of water quality, volume, and cost.

Water Quality

When it comes to water treatment, you might think that one can filter out more contaminants than the other. This holds true for different types of filters, depending on their media. Certain filters, such as RO systems can remove impurities like microorganisms and minerals.

But in the case of under-sink and whole-house filters, both can remove the same impurities and contaminants. This includes chlorine, VOCs, heavy metals, pesticides, chemicals, nitrates/nitrites, and more.

Water Volume

Whole-house water filters win in this department because they feature larger cartridges that can treat more water per day without affecting flow rate. But, this also means that they will take up more room.

With under-sink water filters, they’re only supplying treated water to a single tap. But the best part is that they are small enough to fit in a kitchen cupboard.


In terms of overall cost, under-sink water filters are less expensive than whole-house treatments. An under-sink water filter will typically cost around $100 to $500. It’s also easier to install and maintain than a POE filter so there’s less expense on service and maintenance

Whole-house filters, on the other hand, may cost you around $500 and up, depending on the type of filtration it comes with. Plus, the professional fee for installing one in your home will quickly add up.


Are Under-Sink Water Filters Better?

It really depends on the quality of the water you have at home. If the only issue you have is bad-tasting water, an under-sink filtering system should suffice.

But, if you need filtered water to be distributed throughout your entire home to cater to different purposes like washing, showering, and cooking, then a whole-house filter may be worth the investment.

Is It Worth Getting a Whole House Water Filter?

Before installing a whole-house filter, consider how often and how much chlorine-free water you need for a range of applications. Are you planning to use it for bathing, cooking, and washing all the time? If so, a whole-house water filter would be worthwhile.

However, if you only need it for specialized tasks, such as watering plants, a standard shower filter will do. See all the types of water filters you can get for your home. There are plenty to choose from, depending on your preferences and budget.

Can Whole-House Water Filters Be Cleaned and Reused?

Yes, you can reuse certain types of whole-house filters. Reusing your old water filter cartridge is ideal instead of replacing it with a new one every month. This not only saves you money, but it’s also good for the environment. Make sure to clean your cartridge.

Whole House Water Filter vs Under Sink: Which One Is Right for You?

Deciding on whether to get a whole-house water treatment or install one under your sink boils down to your household needs. It’s always a good idea to consider comprehensive water treatment for your home. But if you don’t have the budget for it, an under-sink water filter will suffice for drinking and cooking.

We hope you found this post helpful in understanding the difference between the two types of filters. If you have more questions, feel free to contact us.

Related Articles

Well Water vs City Water featured image

Well Water vs City Water

Everyone needs water for drinking, cooking, bathing, cleaning, and more. If you’re a homeowner, then you are probably in the middle of deciding between well water vs

Read More »