Also, banks can reverse any transaction from your account if they have a reason for it - for example if they made a mistake - even after it has appeared in your account and even after you've spent the money, leaving you with negative balance in your account. You can trust your account balance only in nominal situations. – Nakedible – 2013-08-01T07:54:00.167

Do note that bank wire transfers can be reversed if the recipient account has not been credited - sometimes up to 2 days later. Always wait for the balance to appear in your account before acting. – Gary Rowe – 2012-11-15T14:23:45.353