Hi- I've luckily been offered a 1+3 studentship for this September from the ESRC. I'm certain I want to do the MSc, but not sure about the PhD, especially as I'd have to commute to the University. In the unlikely case that I don't complete the whole PhD, do I have to repay the ESRC? For example, if I do one or two years of the PhD?

They fund in increments so you'd only be getting money a term in advance. Regarding giving monies back, to the best of my knowledge no.

Thanks. I can't find info on the ESRC website- so they pay six months in advance?

ESRC pay the university and the university pays you (I think this is universal?). So arrangments for payment depend on your institution. For me it is monthly in advance. If I left one week into the month I'd have to pay the three weeks back.