Nse Begins New F&O Pre-Open Trading Window Today, 8 December 2025

The National Stock Exchange has launched a pre-open session for the futures and options segment from 8 December 2025, signalling a significant procedural shift in derivatives trading. 

The new window mirrors the mechanism used in the cash market and is intended to support clearer price formation, smoother liquidity and reduced volatility at the start of the trading day.

Details of the NSE F&O Pre-Open Session

Scope of the Session

The pre-open mechanism applies to index and stock futures within the equity derivatives segment. It is available only for near-month contracts, except during the final five trading days, when the following month’s futures also become eligible.

Order Placement Window

Participants may place, revise or withdraw orders from 9:00 AM until any time between 9:07 AM and 9:08 AM. The exact end of this window can vary within this one-minute range, as specified by the exchange.

Permitted Order Types

During the pre-open phase, both market and limit orders can be submitted. Stop-loss and Immediate-or-Cancel (IOC) instructions are not permitted for this session.

Order Matching Process

From 9:08 AM to 9:12 AM, the exchange conducts an order matching exercise to determine an opening price, also known as the equilibrium price.

• Limit orders are matched against other limit orders.
• Remaining limit orders are then matched with market orders.
• Market orders may be matched among themselves where applicable.

Order Modification Restrictions

Once the matching period begins, no order changes or cancellations can be made.

How the Equilibrium Price Is Set

The opening rate arises from a price point at which the highest tradable quantity can be executed, based on prevailing buy and sell interest.

Treatment of Unmatched Orders

Any limit orders that remain unexecuted after the matching period carry forward into the continuous trading session, maintaining their original time priority.

When Orders May Be Rejected

All orders submitted during the pre-open phase undergo margin checks. If the trader’s available capital does not cover the margin required, the order will not be admitted into the session.

Read More: SEBI Considers Investor Suitability Rules for Derivatives Trading.

Conclusion

The introduction of a pre-open phase for F&O contracts marks a procedural expansion aimed at improving early-session trading conditions. By aligning the derivatives market with the existing cash market framework, the exchange aims to facilitate smoother price formation and more orderly market openings.

Disclaimer: This blog has been written exclusively for educational purposes. The securities mentioned are only examples and not recommendations. This does not constitute a personal recommendation/investment advice. It does not aim to influence any individual or entity to make investment decisions. Recipients should conduct their own research and assessments to form an independent opinion about investment decisions.

Investments in the securities market are subject to market risks, read all the related documents carefully before investing.