A lot of banks are now offering overdraft protection on debit cards. They offer it free and encourage it. If your account ever goes below zero they will allow and authorize any bebit card transaction to go through if you accept this. ` The problem is that they will charge you $34 (Chase amount) per the service. They will only charge you 3 times that day ($102) if you keep using your card. How nice of them. Then if you don't have the money back in your account (plus fees I'm guessing) in 5 days they will charge you $15 extra, and again the same amount every $5 days. So that $5 purchase at the 7/11 may cost you at least an extra $34. If it's offered at your bank you should decline it. If you decline it all that will happen is that your debit purchase will be declined if there is no money in your account. How the government allows this type of scam that I consider theft is bizarre to me. Banks are pushing this too, I've had it done in person. They tell you it's a free service and no cost if you don't use it. Unsuspecting people think it's a good thing because they don't know better.