Do UK citizens have social security numbers? If not, then how do they link your credit score to you?

Answer 1

Its called a national Insurance Number. It is not quite as pervasive as it is in the USA. this can cause problems because they often do credit scores by address so if the info is outdated you can get shafted. I left a trail of devastatiojn behind me when I failed to pay Poll Tax in four cities.

PS: I should mention that I failed to pay Poll Tax because I was a Poll Tax objector, not because I'm tardy about paying bills.