There are only two things you will spend money on your first three weeks at OCS: haircuts and gear at the PX. The PX takes credit/debit cards, so there is no need to bring all of your money in cash. OCS requires that candidates show up with no less than $450 available either through cash or credit.
You will immediately spend between $216 and $244 at the large and small bag issue. Haircuts are once a week and cost $7, as of fall 2007. You will save yourself a headache if you bring a bunch of singles. There is nothing like 50 candidates all trying to get change from their twenty-dollar bills the night before haircuts.
Keep your money in your wallet, which will be secured in your wall or footlocker. The only other thing you should spend money on will be PX calls on haircut day. If you want extra skivvie shorts, an inspection belt, or extra white tape you can buy it there.
Having some extra cash is a good thing. You can help that candidate who is couple dollars short on haircut day. And you won’t need to hit an ATM first thing on liberty, you can go straight to the bar.