yes, that's what I meant. OBC is onboard credit. Basically you buy money to have on your account. You can do this before the cruise, like right before if you'd like. So let's say you buy $500 in credits, it will be on your account when you board. Charges would go against this balance. Only if you use up all this credit would you have to go to GS and put a card on file. If you don't use it all, you go to GS before departing and get the net amount in cash. You run the risk of your charging abilities being cut off if the amount of charges becomes more than what they are able to pre-authorize on the one card. that is why I was thinking that you'd have to keep going back to GS to pay down the account with a different card. Of course, you can pre-pay as much as possible before the cruise so that you won't have much, if any, charges to your onboard account.