Mains water filtration allows homeowners to choose from a multitude of water treatment options ranging from solutions that improve the taste and appearance of water to more complex solutions that remove hardness minerals or ensure the utmost safety of your mains water supply.

Throughout the UK, mains water is considered safe for all household purposes, including drinking or use for cooking. Despite this, some contamination issues cannot be entirely excluded, and water quality may vary significantly from region to region. Some regions may have access to hard water, in other regions water may be treated with substances that could potentially cause health issues on the long run.

All these issues can be easily dealt with thanks to various mains water filtration and water treatment solutions designed for homes and businesses alike, but is there a catch-all mains water filter that works best for water treatment?

Why Filter Tap Water?

“If tap water is safe, why filter it?” you may rightfully ask. Indeed, tap water is held to high quality and safety standards, and it’s treated to remove a host of health-related contaminants, but not all types of contaminants that may be deemed undesirable.

 There are various reasons why you might want to filter tap water including:

  • High levels of sediments that may cause clogging issues in your home appliances;
  • Chlorination, which may dry skin or cause flare ups and irritation in people suffering from a skin condition;
  • Off smells and tastes in your tap water due to chemical disinfection or other issues;
  • Fluoridation;
  • Water hardness;
  • Environmental considerations, etc.

The peculiar taste of tap water is often cited as the number one reason why people frown upon the idea of drinking tap water instead of bottled water, even if bottled water does nothing but add to the already rampant plastic pollution.

By filtering water, removing any contaminants that could cause health issues, or that interfere with the taste of water, switching to tap water can be much easier.

Whatever your stance is on the issue of plastic pollution, another argument in favour of water filtration is its low cost. Filtering water at home will significantly reduce the amount of money you spend on bottled water. Thus, not only that water filtration is environmentally friendly, it’s also less costly and more convenient than bottled water. 

Mains Water Filtration

There are many ways to go about filtering your mains water supply, but before you can determine which option to choose, you first have to determine what are the ingredients in your water supply that shouldn’t be in your water or that you simply don’t want to have in your drinking water.

Water Testing

It may seem like too much of a hassle or an extra expense to get your water tested, but it’s a necessary step, especially if you don’t want to invest in a filter that is not designed to solve your water contamination issues or one that’s an overkill for the problems you are facing.

To have your water tested for its quality you can opt for the services of a local lab, or you can order an at-home water testing kit to carry out the test yourself.

Once you have a clear overview of the types and levels of contaminants present in your mains water, you can almost start your search for a mains water filter, because there’s one more step to consider:

Determining Your Filtered Water Needs   

There are many ways to determine your filtered water needs, but the most important question you should ask yourself is this: Do you want filtered water only when you turn on your kitchen tap, or also when you turn on all the other taps in your home (bathroom tap, shower, etc.)?

It’s important to think this through, because it will determine the type of filter you’re going to get. If you want filtered water only in your kitchen a point-of-use (POU) water purification system or undersink filter is all you need. But if you want filtered water in your entire home, a point-of-entry (POE) or whole house mains water filtration solution is your best choice.

Next, let’s see what each option can and can’t do.

POU Filters

As we’ve already cleared it up, undersink filters or POU filters filter water that goes through your kitchen tap. While most of these filtration units are installed undersink, there are countertop options as well. Countertop filters don’t require the installation of an additional tap, but undersink filters require that you install a filter tap next to your existing kitchen tap.

POU Filters Can:

  • Eliminate chlorine, VOCs, bacteria, viruses, heavy metals, and all sorts of other contaminants;
  • Reduce limescale;
  • Be multi-stage systems comprised of as many as 7 filter cartridges, all designed to fit under your kitchen sink.

POU Filters Can’t:

  • Filter your home’s entire water supply;
  • Work independently of water pressure (except for gravity water filters).

POE Filters

The rationale behind point of entry filters is to filter all the water you use in your household. The whole house filter is installed on your water line just before water is distributed throughout your home, this ensures that you get filtered water regardless of the tap you decide to turn on in your home.

POE Filters Can:

  • Remove all sorts of health-related and non-health related water contaminants;
  • Be multi-stage systems combining various filter cartridges;
  • Reduce limescale;
  • Allow you to keep using all your existing taps.

POE Filters Can’t:

  • Fit into small spaces;
  • Operate without water pressure unless they’re an UV filter.

POE filters are considered the more economical option and more convenient option compared to having multiple POU filters installed throughout your home.

Which Mains Water Filter is Best?

The answer to this question depends on what your needs are. If you live in a small apartment, you probably don’t need all the bulky hardware that comes with a whole house filter. But if you live in a large household, you should probably consider a whole house filtration system.

The choice of filter will also depend on the quality of the municipal water. If it’s better to filter all the water supplied to your home — because of the nature and levels of contaminants — you should opt for a POE filter.

Alternatively, you can install a POU filter in your kitchen, but also other POU filters like shower filters, inline filters, etc. for other water outlets in your home.

Make sure the filters you do decide to install are designed to remove the contamination issues you’re struggling with. Also, buy filters and replacements only from reputable vendors.

Installing a water filter is not the only step you have to take to ensure clean and safe water in your home. You also have to maintain that filter by replacing cartridges, cleaning the filter (if applicable), and monitoring the quality of your water.

Any sudden changes in the taste or odour of your filtered tap water may be an indication that you have to replace the filters in your unit.

Other Mains Water Treatment Solutions

Undesirable contaminants are not the only issue homeowners deal with when using tap water. Water hardness is a very common problem throughout the UK, and some households may need special water treatment solutions to get rid of hard water problems.

Water softeners are one solution to the problem. These units remove calcium and magnesium ions by swapping them for sodium ions. Being free of hardness causing minerals, soft water will no longer be a threat to the health of your home appliances.

Another option to deal with water hardness is to inhibit the build-up of minerals by interfering with their ability of precipitate and stick to surfaces. This can be achieved through limescale inhibitors, which are special filters that can alter the crystal structure of hardness minerals.

Both systems can be used in residential settings, depending on the severity of the problem and the particular requirements of each home. Limescale inhibiting water filters are less maintenance intensive, while water softeners require more maintenance.


Filtering tap water may not always be necessary, but it’s a worthwhile investment if you’re considering switching to tap water as your only source of drinking water. Filters remove toxic substances and artificially added chemicals that are undesirable in your drinking water. Some filters also remove the minerals responsible for water hardness, thus, inhibiting limescale build-up.

Filtering municipal water is the most convenient and safest way to give up bottled water and switch to the more economical and eco-friendly tap water.