Water filters for the UK home: do you need one, and which type?

Is UK tap water actually safe to drink?

Yes. Let's clear that up first, because a lot of filter marketing leans hard on making you feel otherwise.

Public mains water in England and Wales is overseen by the Drinking Water Inspectorate, the independent regulator set up in 1990. Scotland and Northern Ireland have their own equivalents, but the principle is the same across the UK. Your water company has to meet the standards in the Water Supply (Water Quality) Regulations, which set legal limits for more than 40 things, from bacteria and metals to pesticides and nitrates. Those limits are built with wide safety margins on top.

And the checking is relentless. Water companies run millions of tests a year, and more than 99.9% of them meet the standards. E. coli, the bug everyone worries about, simply isn't allowed to be present at all. In practice, UK tap water is about as boringly reliable as public services get.

So why do so many people filter it anyway?

Because "safe" and "pleasant" aren't the same thing, and a filter can move the second dial. Here are the honest, everyday reasons people fit one.

Taste and the chlorine smell. Water companies add a small amount of chlorine to keep the supply free of bugs all the way to your tap. It does its job, but some people can smell or taste it, a bit like a faint whiff of a swimming pool. Carbon filtering takes most of that away.

Hard water and limescale. If you're in the South East, the Midlands or East Anglia, your water is probably hard, meaning it carries a lot of dissolved calcium and magnesium. That's the chalky scale on your kettle and the film on your tea. It's completely harmless to drink. It's just a nuisance, and some people prefer softer-tasting water.

Older plumbing. In homes built before about 1970 there may still be old lead pipework hanging around. More on that below, because it's worth being accurate rather than alarmed.

A general wish to reduce the extras. Microplastics and PFAS ("forever chemicals") are in the news, and some people would rather filter than not. That's a reasonable personal call, as long as you know what you're actually buying.

Filtering UK tap water is about preference, not rescue. You're polishing something that's already safe.

What about lead, microplastics and PFAS?

This is the part where honesty matters most, so let's be measured.

Lead. Lead pipes were phased out and eventually banned, but properties built before roughly 1970 can still have lead sections, underground or inside the house. Water companies treat the supply with a phosphate dose that coats the inside of pipes and stops lead dissolving into the water, and hard water forms its own protective scale that helps too. The people most sensitive to lead are babies and young children. So if your home is older and you're not sure what your pipes are, especially with little ones about, the sensible move is simple: ask your water company to test the water at your kitchen tap. It's usually free, and it tells you whether you've got a real issue or nothing to fix.

Microplastics. There's no UK standard for microplastics in drinking water, largely because the treatment already in place removes the overwhelming majority of tiny particles. It's an active area of research, not an established danger from your tap.

PFAS. These are the man-made "forever chemicals" that turn up in the environment. The Drinking Water Inspectorate has set tiered guidance for water companies to monitor and act on PFAS, and the rules here are still developing. For the ordinary mains customer, this is something regulators are watching closely on your behalf, not a reason to panic-buy a filter. If you want to reduce PFAS at home anyway, reverse osmosis is the type that does it best.

Which type of water filter is right for you?

There's no single "best" filter, only the right tool for the job you actually have. Here's what each type does, roughly cheapest to dearest.

Jug filters. A carbon cartridge in a plastic jug you keep in the fridge. Cheap, no plumbing, great for the taste and chlorine jobs. They don't soften water or reliably remove metals. Cartridges need changing every month or so.

Tap-mounted filters. A small carbon unit that screws onto the end of your tap and switches between filtered and normal. Similar cleaning power to a jug, more convenient, slightly more to buy. Not every tap fits them.

Under-sink carbon filters. A larger carbon cartridge plumbed in under the worktop, feeding a dedicated tap or your existing one. More capacity and better flow than a jug, so a good step up if you filter a lot and hate refilling. Still a carbon filter at heart, so still mainly a taste-and-chlorine device.

Reverse osmosis (RO). The thorough one. Water is pushed through an extremely fine membrane that strips out the widest range of contaminants, including most metals, PFAS and microplastics. It also removes the harmless minerals, so some people find the water tastes "flat", and it wastes some water in the process. Sat under the sink with its own tap. Genuinely useful in specific cases, overkill for most regulated mains supplies.

Gravity filters (Berkey-style). Countertop units where water drips through candle-style elements, no plumbing or electricity needed. Popular with off-grid and power-cut-conscious folk. Quality and claims vary a lot between brands, so buy on independent testing rather than the label. Handy where you've no mains pressure, less necessary if you have.

Whole-house filters. Fitted where the mains enters the property, so every tap, shower and appliance gets treated water. Usually chosen for hard-water scale protection across the whole house, or on problem supplies. The biggest install and the biggest spend.

What's worth the money, and what's just marketing?

Match the filter to the actual problem and you'll rarely overspend.

If your only gripe is taste or the chlorine smell, a carbon jug or tap filter is all you need, and anything dearer is money you didn't have to spend. If it's limescale you're fighting, no carbon filter will help. You want a water softener or a scale-reducing cartridge, or RO for drinking water specifically. If you've genuinely older plumbing, get the tap tested before you buy anything, because the answer might be "replace a pipe", not "fit a filter".

Reverse osmosis and whole-house systems are real, capable kit. They're just aimed at real problems: private supplies, very hard water across a whole house, or a personal decision to filter as much as possible. Buying one to "make safe water safer" is the classic case of solving a problem you don't have.

1. 1

   Name the actual problem

   Is it taste, chlorine smell, limescale, old pipes, or general peace of mind? Write it down. The problem picks the filter, not the other way round.

2. 2

   Check whether your water is hard

   Look up your postcode on your water company's site, or just look at your kettle. Hard water rules carbon filters out for scale, and points you at softening or RO.

3. 3

   If the house is pre-1970, test before you buy

   Ask your water company to test your kitchen tap for lead, especially with young children at home. It's usually free and settles the question.

4. 4

   Start cheap and specific

   For taste, begin with a carbon jug. Only move up to under-sink, RO or whole-house if a specific problem genuinely needs it.

5. 5

   Budget for the ongoing cost

   The cartridges, not the unit, are the real spend. Factor in replacements every few months, or a filter quietly stops doing anything at all.

What if I'm on a private or off-grid supply?

Everything above assumes you're on regulated mains water. If your water comes from a borehole, well, spring or stream, the picture changes completely. Private supplies aren't tested by a water company, and the responsibility for safe water sits with you and your local authority, who carry out risk assessments. These sources can carry bacteria, parasites and contamination from the surrounding land, so they typically need proper multi-stage treatment and disinfection, not just a carbon jug.

That's a whole subject of its own, from testing regimes to UV treatment. If that's you, start with our guide to off-grid and private water systems in the UK, then treat and test accordingly. For a private supply, filtering isn't a nice-to-have. It's the job.