If your phone is unlocked you can get a Digicel or Lime sim. If you want to save time and a visit to one of the stores, you can order a LIME sim from https://www.mrsimcard.com/caribbean/s-limebvi.html.

It's worth calling ahead as some of the stores do run out of sim cards. We've seen that happen at the Virgin Gorda Digicel store.

Cheers, RickG