One important thing to consider is that your online account probably won't replace your traditional checking account. "There are limits on how many withdrawals you can make from the account each month, so you can’t use it as a checking account, but the money is accessible if you need it in a pinch," McBride says. Federal regulations limit the number of withdrawals from online banks to six times per statement cycle. Go beyond that, and you'll be subject to a fee, for example, $10 per transaction at places like Ally Bank