I see what you mean now San.
They definitely do not run SMALL. Their numbers are just different from ours. They simply use British sizing, which usually begins at an 8 (occasionally a 6 but I don't see this very often). Personally, I do not find British and US sizing to be apples to apples. If it were, sizes would be as follows:
US 0 = UK 8
US 2 = UK 10
US 4 = UK 12
US 6 = UK 14
US 8 = UK 16
etc.
But in my experience, it doesn't quite match up. I am a US size 2/4 and I take a UK 8 or 10. I have never worn a 12. My friend who spends a lot of time in England with her mother is a US size 6 and wears a UK size 12.
Back to Boden: I say their sizing runs big because their size 8 is the equivalent of a US size 4. A UK 8 should really not be bigger than a US 2.
French Connection is more TTS for me. I wear a UK 10 there.
Sometimes when my friend from Australia comes for a visit, we swap clothes. She is the same size as me, and most of her clothes are 8's or 10's as well (Aussie sizing also follows the UK system).
I hope that made things clearer...