About 1/4 of students live in the parental home, even more so if they are working class. This source has 45% of 'poorer' students living at home.
Research from our Department of Education finds an increase in 'commuter students' living at home and travelling a significant distance to university.
www.bath.ac.uk
So, it will vary quite a bit depending on the university and its intake, but the idea of a majority of students all rolling in from 2 or 3 university owned halls has gone. Increasing number of privately owned halls for one thing.