Your trade transactions with a stock exchange will only be processed during business hours. The Bombay Stock Exchange (BSE) and the National Stock Exchange (NSE) follow the same timings.
Markets are open between 9:15 a.m and 3:30 p.m from Monday through Friday. Stock exchanges are closed on predefined days, and you can find out the dates on the official calendars of the stock exchange.
However, there are sessions that open even before 9:15 a.m.
i) 9 a.m - 9:08 a.m: this pre-opening session allows transactions to be placed by investors. The transactions placed in this duration are given preference over others and are cleared once the actual trading starts. The trade orders can be cancelled or modified by investors ,and one cannot place any trade order once this window expires.
ii) 9:08 a.m - 9:12 a.m: in these four minutes, the prices of the securities are determined by matching the demand and supply prices to ensure there is accuracy in the transactions made by investors. The final prices are determined, through a multilateral order matching system, at which the actual trading starts once the markets open for regular trading. The price matching is critical in arriving at the price at which the securities are transacted when the regular trading starts 9:15 a.m onwards.
iii) 9:12 a.m - 9:15 a.m: This window exists to facilitate a smooth transition between pre opening and normal trading sessions. No orders can be placed in this duration, and those placed between 9:08 a.m and 9:12 a.m cannot be modified or cancelled in this duration.
Post 9:15 a.m, investors can place trade orders through 3:30 p.m. The trades placed in this window follow a bilateral order matching system.