Best Water Filter UK 2026: Brita vs Water2 vs System 40, Whole House & Reverse Osmosis

If you have decided you want better tasting or more extensively filtered drinking water at home, choosing the filter is often the difficult part.

Do you start with a Brita water filter jug? Is it worth moving to an under-sink water filter such as Water2 or System 40? Would you be better filtering every tap with a whole house water filter? Or should you go further and choose reverse osmosis?

They will all improve your water, but they work in different ways and the experience of owning each one is just as important as the filtration itself.

In our latest video, we discuss five different approaches to home water filtration, including Brita MAXTRA PRO, Water2 Pod 2.0, System 40, BT65 whole house filtration and the RO5EW reverse osmosis system.

We look at what each one reduces, how often the filters need replacing, installation, running costs and what each system is actually like to live with.

We also put three of the drinking-water filters through a blind taste test at the end.

Watch the full water filter comparison

Is UK Tap Water Safe to Drink?

UK tap water is heavily regulated. The Drinking Water Inspectorate reported that 99.97% of regulatory samples from public water supplies in England met the required standards in 2025, across more than 3.5 million samples.

However, meeting drinking-water standards does not mean every person will necessarily want the water exactly as it arrives from the tap. Contaminants can still exist in the water supply even if it is deemed safe to drink.

Chlorine is deliberately used to maintain hygienic conditions as water travels through the distribution network. This is why you notice its taste or smell when drinking unfiltered tap water.

There are also substances such as lead, PFAS, pesticides and other chemical parameters that are monitored as part of UK drinking-water regulation.

In 2025, for example, there were 60 lead compliance failures from 14,122 samples, with older lead pipework and internal plumbing remaining the main source.

PFAS are also receiving considerably more attention. More than 666,000 individual PFAS analyses were carried out across England and Wales during 2025.

So you know you want to improve the taste and quality of your water at home. Where do you start?

Brita MAXTRA PRO: The Easiest Place to Start

Brita is probably the most familiar option in this comparison. Fill the jug, wait for the water to pass through the cartridge and put it in the fridge.

The MAXTRA PRO combines activated carbon with ion-exchange resin. Brita says the activated carbon reduces chlorine and substances that affect taste, while the ion-exchange resin reduces metals including lead and copper as well as some carbonate hardness.

Current UK guidance from Brita rates a MAXTRA PRO cartridge for up to four weeks or 150 litres, although actual life will naturally depend on water conditions and use.

Costco currently lists a 12-pack of MAXTRA PRO All-In-1 cartridges at £42.99, giving a relatively inexpensive route into filtered drinking water.

The trade-off is convenience.

If you are drinking a lot of filtered water, filling bottles, cooking and making hot drinks, you may quickly get tired of repeatedly filling a jug and waiting for it to filter. We also found that the jug we tried didn't fit in our fridge door.

An under-sink filter is a massive upgrade over a filter jug as it gives you filtered water on tap.

Water2 Pod 2.0: Filtered Water Straight From Your Existing Tap

The Water2 Pod 2.0 moves the filtration underneath the kitchen sink.

Rather than filling a jug, the Pod connects to your cold water supply and lets you use your existing kitchen tap.

The system uses activated carbon filtration combined with an ultrafiltration membrane, and unlike reverse osmosis it retains minerals such as calcium and magnesium.

One of Water2's biggest advantages is simply the ownership experience.

There is no jug on the worktop or in the fridge. Once fitted, you turn on your existing tap and filtered water comes out.

Its main capsule is replaced approximately once per year, with the current replacement priced at £99 (as of September 2026).

There is also a separate fluoride-reduction option if reducing fluoride is specifically important to you.

For somebody moving away from filter jugs who wants a neat, relatively simple under-sink setup, Water2 makes a compelling case. We also liked how small the filter was and it's very simple to change.

Water2 vs System 40: Two Different Approaches to Under-Sink Filtration

This is probably the closest direct comparison in the video.

The System 40 is also fitted underneath your kitchen sink and, like Water2, filters the water while retaining its naturally occurring dissolved minerals.

System 40 is supplied by East Midlands Water Company, so we have deliberately focused our comparison on measurable differences such as capacity, long term cost and installation rather than pretending this is an anonymous laboratory test.

The filtration construction is different.

System 40 uses silver-impregnated coconut-shell activated carbon together with a Vion F 10-micron pre-filtration screen and cyclone separator.

Its current published reduction list includes chlorine, lead, sediment and larger microplastic particles, pesticides, herbicides, THMs, PFOS and selected PFAS compounds, VOCs and selected pharmaceutical and hormone residues.

Both will massively improve your tap water, but a big difference is how often you have to think about the filter.

Up to 40,000 Litres or Three Years

The System 40 BT1 cartridge is rated for up to 40,000 litres or three years, whichever comes first.

A replacement BT1 currently costs £195 for another three-year cycle.

By comparison, Water2's current £99 annual replacement works out at £297 across three annual replacement cycles at today's prices.

Prices can obviously change, which is why the video uses the prices available at the time of filming.

There is another difference in installation.

The System 40 comes with a dedicated drinking-water tap, connection hoses and a self-piercing mains valve, giving you flexibility around how the filtered water supply is configured.

There is also an optional fluoride reduction version, like the Water 2 Pod 2.0.

System 40 is aimed more towards somebody prioritising higher capacity, a much longer replacement interval and additional installation options.

BT65: What If You Want Every Tap Filtered?

Brita, Water2 and System 40 are principally point-of-use drinking-water solutions.

A BT65 whole house water filter is fitted to the incoming mains water supply before the water travels around the property.

That means filtered water can reach your kitchen, bathrooms, showers, baths and connected appliances from one central system.

The standard BT65 uses silver-impregnated coconut-shell granular activated carbon with twin sediment filtration. It reduces chlorine, unwanted tastes and odours, sediment, lead and selected heavy metals, THMs, pesticides, herbicides and many VOCs while retaining naturally occurring minerals.

Its biggest difference is scale. The standard model is rated for up to 650,000 litres or around three years, depending on household usage and incoming water quality.

For a home where the aim is not just better drinking water but also filtered shower and bathing water, a whole-house filter begins to make much more sense than installing individual filters everywhere.

There is also an optional fluoride-reduction version.

Does the BT65 Stop Limescale?

This is an important distinction that gets confused online. No water filter will completely stop limescale despite what some companies may claim.

The BT65 retains calcium and magnesium, so it does not soften hard water or stop limescale.

If limescale is your main problem, you need to look at a water softener instead.

Reverse Osmosis: A Completely Different Type of Water Filtration

Reverse osmosis is the most extensive form of drinking-water treatment in the comparison.

The RO5EW shown in the video uses multiple sediment and carbon stages before water reaches an RO membrane rated to 0.001 micron, followed by a final activated carbon polishing stage. It can also be specified with a remineraliser.

Unlike the carbon filters above, reverse osmosis substantially reduces dissolved mineral content as well.

The RO5EW product specification states reductions of more than 98% for dissolved minerals such as sodium, calcium and magnesium.

The result is highly purified drinking water.

Some people specifically choose RO because they want very low dissolved-solids water, but others prefer the taste and mineral profile of carbon-filtered water.

An optional remineralisation cartridge can be fitted after the RO process to add selected minerals such as calcium and magnesium back into the finished water. The current EMWC cartridge has an approximate capacity of 6,000 litres or 12 months.

The Downsides of RO

Reverse osmosis gives you extensive purification, but the ownership experience is very different from a System 40 or Water2.

The RO5EW needs more under-sink space, uses a pressurised storage tank and requires a waste connection because part of the incoming water is discharged as reject water during membrane filtration.

There are also several consumable filters. The sediment and carbon stages are approximately six-month replacements, while the RO membrane has an approximate 18-month interval.

So choosing the filter with the most extensive purification is not automatically the same as choosing the best filter for your home.

Quick Comparison: Which Type of Water Filter Suits You?

	Brita MAXTRA PRO	Water2 Pod 2.0	System 40	BT65	RO5EW
Type	Jug	Under sink	Under sink	Whole house	Reverse osmosis
Filtered water	Jug only	Existing kitchen tap	Drinking tap / suitable tap setup	Whole property	Dedicated drinking tap
Minerals retained?	Some hardness reduced	Yes	Yes	Yes	Most substantially reduced
Typical filter interval	Up to 4 weeks	Around 1 year	Up to 3 years	Up to 3 years	Multiple intervals
Fluoride option	Not specialist fluoride filtration	Optional add-on	Optional	Optional	RO reduces fluoride
Waste drain required	No	No	No	No	Yes
Best suited to	Low commitment	Existing tap convenience	Long-life under-sink filtration	Whole-house filtration	High-purity drinking water

Which Water Filter Tastes Best?

Three samples were prepared without telling the team which was which:

Brita, Water2 and System 40.

The samples were tasted blind and compared before the identities were revealed.

Watch the full video to see which filter won the blind taste test.

 

So, What Is the Best Water Filter in the UK?

It depends on your budget and setup in your home.

A Brita jug remains a sensible, inexpensive introduction to filtered water.

Water2 is a low price point for entry to the world of filtered water. It removes the jug entirely and gives you filtered water from your existing kitchen tap.

System 40 takes the under-sink concept further towards long filter life and high capacity.

BT65 makes sense when you want filtration throughout the property rather than at one drinking-water point.

And reverse osmosis is for somebody who deliberately wants a much more extensive reduction in dissolved substances and accepts the additional installation, filter changes and waste-water connection that come with it.

If you are still not sure, speak to the East Midlands Water team. We can help you work out whether you need a simple drinking-water filter, whole-house filtration, reverse osmosis or something completely different.