A trading halt happens when the stock exchange stops trading specific security for a certain period of time, usually one hour but can last indefinitely. This halt is ordered by NASDAQ and/or NYSE, and all brokerages must comply with the halt. Trading halts can happen at any time of the day and sometimes multiple times during the day. If the stock has resumed trading during normal trading hours, Stockpile customers can place a new trade for that particular security. However, if the halt continues, then the order will be canceled.