If you fancy shopping in person, I’d highly recommend Katherine Bird on Battersea Rise. They have a wonderful range of formal dresses and different brands to anything you’d usually see on the high street!

I’ve found silkfred has LOADS of different options and best of all free delivery and returns (over £50 I think).

Try Lux Fix.  Discovered it recently and it's full of lovely stuff and great customer service too which is always a bonus!

Currently trawling through department store websites…