Question:
Is it possible to fit a Brita water filter system on a bathroom faucet (not threaded) ?

The system they sell in Sav-On and stores like that all show the filter fitting over a typical kitching sink faucet. Does an adapter or something exist for use in a bathroom?

Answer: bathroom fixtures are normally connected to a tank. Water can be stored there for sometime before it is fully used. so the water isnt clean to filter it only.Water filters are fitted to the incoming mains water supply. As it is not customary to have mains water in a bathroom (UK ) then they don't make provision for it.In the USA they DO have mains water, so it would be necessary to have a plumber fit a tee-off valve with suitable connections for it to work, and you would have to have a place to secure it.