Guides

Water filter guides for UK homes

Practical guides for people choosing a kitchen water filter: how each type fits, what it takes to keep running, and what to ask before buying. They deal with types and decisions rather than individual products.

Choosing a type

• Under-sink water filters

  Connected to your existing tap, a dedicated tap or reverse osmosis; the clearance you need to change cartridges; renting; plumbing quotes; and one, three and five-year costs.

• Countertop water filters

  Refill, tap-attached and plug-in types; the worktop, socket and storage space they take; capacity and cleaning.

• Reverse osmosis water filters

  How the membrane works, why water goes to drain, pressure and power, countertop versus under-sink, the mineral question and what the official guidance says.

Understanding the claims

• Hard water and limescale

  What limescale is, why carbon filters and softeners aren’t the same thing, and how to read a scale-reduction claim.

• Water filter certifications

  What NSF/ANSI 42, 53 and 58 and WRAS approval each cover, and how to check a certificate against the exact model.

Keeping it running

• Water filter replacement

  How change dates work, finding the exact cartridge code, and counting replacements in the cost.

Compare running costs · Check our sources and evidence labels