Mumbai: The National Stock Exchange has revised its pre-open session framework from September 7, 2026. The session will continue from 9:00 am to 9:15 am, but order entry and matching will now occur in separate phases.
The biggest change is that market orders cannot be placed between 9:05 am and 9:10 am. During this period, investors can place, modify or cancel only limit orders.
What happens from 9:00 am?
Between 9:00 am and 9:05 am, investors can place both market and limit orders. They can also modify or cancel orders during this window.
Therefore, investors wishing to place a market order during the pre-open session will have only five minutes to do so.
From 9:05 am to 9:10 am, the exchange will accept only limit orders. These orders may be modified or cancelled, but market orders will not be allowed.
Opening price discovery
Order matching and trade confirmation will take place between 9:10 am and 9:12 am. The opening price will be determined during this phase, and eligible buy and sell orders will be matched.
Earlier, the matching process ran from 9:08 am to 9:12 am. Under the revised framework, it will begin at 9:10 am.
The final three minutes, from 9:12 am to 9:15 am, will serve as a buffer period before regular continuous trading begins.
Which securities are covered?
The rules are not restricted to futures and options traders. They apply to eligible securities in the equity cash market’s pre-open session.
These include mainboard and SME shares, partly paid-up shares, Infrastructure Investment Trusts and Real Estate Investment Trusts.
Why has NSE changed the rules?
The revision aligns the pre-open mechanism with the Closing Auction Session introduced on August 4. The auction combines buy and sell orders to determine closing prices for cash-market securities that have derivative contracts.
NSE expects the new structure to improve coordination between the cash and derivatives segments. Investors must now carefully check the timing and order type before trading.
