Pre-open session changes from 7 September 2026: what actually changes for traders
From Monday, 7 September 2026, the pre-open session on NSE and BSE splits into two parts. Market orders will be accepted only in the first five minutes. After 9:05 AM, limit orders only.
The window itself stays where it is, 9:00 AM to 9:15 AM. What changes is what you can place, when you can place it, and when order entry actually shuts.
This comes from SEBI circular HO/47/11/11(3)2025-MRD-POD2/I/2765/2026 dated 16 January 2026, the same one that brought in the Closing Auction Session on 3 August. NSE put out the operational details in its circular of 29 May 2026. The revised pre-open applies to the equity cash segment, stock futures and index futures on both exchanges.
How the pre-open works today
| Time | What happens |
|---|---|
| 9:00 AM to 9:08 AM | Market and limit orders can be placed, modified or cancelled. AMOs in equity and current-month index and stock futures are forwarded to the exchange. |
| 9:08 AM to 9:12 AM | Order matching and trade confirmation. |
| 9:12 AM to 9:15 AM | Buffer period before continuous trading starts. |
How it works from 7 September
| Time | What happens |
|---|---|
| 9:00 AM to 9:05 AM (Session 1) | Market and limit orders can be placed, modified or cancelled. AMOs in equity and current-month index and stock futures are forwarded to the exchange. |
| 9:05 AM to random close (Session 2) | Limit orders only. You can place, modify or cancel limit orders. Market orders can't be placed, modified or cancelled at all. |
| Random close to 9:12 AM | Orders are matched and the equilibrium price is worked out. Orders entered here sit in requested mode. |
| 9:12 AM to 9:15 AM | Transition into the continuous trading session. |
The random close is the part worth reading twice. Order entry doesn't stop at a fixed time. The system shuts it at some point between 9:08 AM and 9:10 AM, and nobody knows in advance which second it will be. That's deliberate, and it's the same design already running in the Closing Auction Session at the other end of the day. If you're used to sitting on an order till the last moment, there's no longer a last moment you can count on.
Where pre-open doesn't apply
Three exclusions to keep in mind:
- Option contracts on indices and stocks
- Futures of an underlying security on its ex-date of a corporate action arising from a scheme of arrangement
- Stop loss orders, orders with disclosed quantity, and IOC orders
How the opening price gets fixed
Both market and limit orders go into the matching. The exchange looks for the price at which the maximum quantity can be executed, and that price becomes the equilibrium price, which is your opening price.
Take a simple case:
| Order price | Quantity that would match |
|---|---|
| ₹2,507 | 2,000 |
| ₹2,506 | 7,500 |
| ₹2,505 | 6,000 |
₹2,506 clears the largest quantity, so ₹2,506 opens the stock.
Through the session, your terminal or broker app will keep showing indicative numbers in the market depth or get quote section: indicative index price, indicative equilibrium price, indicative quantity, cumulative buy and sell quantities, and the imbalance quantity.
What to change in your routine before Monday
If your habit is to fire a market order somewhere around 9:07 to make sure you're in at the open, that habit stops working next week. Anything you want matched at market price has to go in between 9:00 and 9:05. Miss that window and your only option is a limit order, priced by you, with no guarantee of a match.
For clients who place orders through you, this is worth a one-line message before Monday morning. The first day of any timing change tends to be the one that generates the calls.
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