Pre Open Session for F&O Trading
National Stock Exchange (NSE) is going to start pre-open session for equity derivatives (F&O) segment from December 8, 2025. The purpose of this new change is to make it easier to enter the market and increase price transparency. Traders will soon see the benefit of this in price discovery. That means, the implementation of pre-open session will be limited only to single stock futures and index futures.
Timings and structure of pre-open session
The pre-open session will run from 9:00 am to 9:15 am and call auction mechanism will be adopted. This 15 minute session is divided into three parts. In the first phase, traders can place, change or cancel orders. This order entry period will start at 9:00 AM till 9:08 PM and the system may close it randomly at 7th or 8th minute.
In the second phase, order matching and trend confirmation takes place. From 9:08 am to 9:12 am the system will decide the equilibrium price and orders will be matched on that basis. During this period, no new order will be allowed to be placed or changes made. The third phase consists of a buffer period from 9:12 to 9:15 pm, which fills the gap between the pre-open session and continuous trading hours.
Which contracts will be included?
The pre-open session will be applicable on futures contracts of the current month. This will also be applicable on next month’s futures during the last five trading days before expiry. Keep in mind that this session will not be applicable on distant month (M3), spread contracts, option contracts and ex-date futures.
Orders and Trading Rules
Both market and limit orders can be placed during the order entry period, but special orders like stop-loss and IOC will not work during this period. Traders will get indicative prices, equilibrium data and demand-supply information in real-time. In the order matching phase, the system will determine a single equilibrium price and orders will be matched according to a certain sequence.
Objective and benefits of NSE
This new system is expected to bring many improvements in the F&O market. Once the market opens, liquidity will increase, price transparency will increase and volatility will reduce. Apart from this, traders will get the opportunity of better price discovery in the initial period.