The girls made sure they weren't seen in the same outfit twice and switched their red carpet looks for more, er, party appropriate ensembles.
Ellie ditched her dramatic pink Vivienne Westwood gown for a sexy black dress with cutout, sheer panelling and accessorised with a pair of Beats by Dre headphones.
Lorde swapped her sequinned number for a simple LBD. She wiped of her usual dark lippy in favour of a lighter shade too.
Katy slipped out of the Julien MacDonald dress she wore to present an award and wore a gold lace two-piece instead.
WANT TO SEE MORE FROM THE BRITS? Check out all the best red carpet looks in the gallery below...