Catit Flower Fountain (3L)

The Catit Flower Fountain is the default recommendation for a reason: at around £22 it is one of the cheapest ways to give a cat moving, filtered water, and it is among the most-reviewed cat fountains sold in the UK. The 3-litre reservoir holds enough for a weekend away, three flow settings (from a gentle surface flow to a livelier bubbling top) suit fussy drinkers, and the triple-action carbon filter helps keep the water fresh. The trade-off versus a pricier PetSafe Drinkwell is material: the Catit is plastic, so it shows scale sooner and needs regular cleaning to avoid slime, and reviewers note the pump can hum if the level drops too low. For most givers, though, the low price, wide availability and strong aggregated feedback make it the safest crowd-pleaser on this list.