Rumer joins Mencap's Little Noise Sessions 2010 line-up
She'll support Paolo Nutini on 16 November
The star will play the Union Chapel in Islington, London on Tuesday 16 November.
Welsh crooner Tom Jones heads up the music festival, which will celebrate its fifth birthday this year, with support from Lauren Pritchard while new group Hurts will perform as well.
Little Noise Sessions presale tickets go on sale to the official website subscribers at 9am on Wednesday 13 October.
Tickets will then go on general sale at 9am on Friday 15 October.
Click here to subscribe to Little Noise Sessions for £6 with the fee going straight to Mencap.
Mencap's Little Noise Sessions 2010 will run from 15-20 November.