Here is a list of roulette bonuses you can claim for free.  There are wagering requirements as casinos are not charities.  They are there to entice you to join.  However, if you are lucky, you can walk away with some free money.

£11 free with Ladbrokes.

T&Cs apply, 18+

£20 Free with Gala/ Coral Casino

T&Cs apply, 18+