NSE Revises Pre-Open Session Structure From September 7, 2026

From September 7, 2026, NSE will change the way orders can be placed, modified and cancelled during the pre-open session. While the total session time will remain unchanged at 9:00 am to 9:15 am, the internal stages will be reorganised.

During the first phase from 9:00 am to 9:05 am, traders will be able to place, modify or cancel both market and limit orders. From 9:05 am to 9:10 am, only limit orders will be accepted, while market orders will be rejected.

NSE Pre-Open Session Timings and Order Rules

The revised pre-open session will follow four stages:

Pre-Open Stage	Time	Key Activity
Phase 1	9:00 am–9:05 am	Market and limit orders can be placed, modified or cancelled
Phase 2	9:05 am–9:10 am	Only limit orders can be placed, modified or cancelled
Order Matching	9:10 am–9:12 am	Orders matched and opening price determined
Buffer Period	9:12 am–9:15 am	Transition to regular trading

The exchange may also randomly stop order entry during the final two minutes of the second phase. Order matching will begin at 9:10 am under the revised framework, compared with 9:08 am under the existing structure.

NSE Pre-Open Session and Opening Price Discovery

The pre-open session operates through a call auction mechanism, under which orders are collected before being matched to determine the opening price. The framework covers securities in the equity market, including SME securities, partly paid-up securities, InvITs and REITs.

The changes are intended to make the opening price-discovery process more consistent with the Closing Auction Session. NSE's current information page also lists updated FAQs for the pre-open session in the equity derivatives segment applicable from September 7, 2026.

NSE Pre-Open Session Key Highlights

Effective Date: September 7, 2026.
Pre-Open Session: 9:00 am to 9:15 am.
Phase 1: 9:00 am to 9:05 am, with market and limit orders allowed.
Phase 2: 9:05 am to 9:10 am, with only limit orders allowed.
Order Matching: 9:10 am to 9:12 am.
Buffer Period: 9:12 am to 9:15 am.
Market Orders in Phase 2: Will be rejected.
Order Entry Closure: NSE may randomly close order entry during the final two minutes of Phase 2.
Key Objective: To align the opening price-discovery mechanism more closely with the Closing Auction Session.

What to Watch Next

Traders may need to account for the revised timing when placing or modifying orders during the NSE pre-open session.

Market participants can watch how the changes affect order placement and opening price discovery after implementation.

Investors may also track further NSE updates relating to the pre-open and closing auction mechanisms.

Disclaimer

Investments in the securities market are subject to market risks. Read all related documents carefully before investing. Registration granted by SEBI, and certification from NISM in no way guarantee the performance of the intermediary or provide any assurance of returns to investors. Choice Equity Broking Private Limited: SEBI Reg No. Broking - INZ000160131 ( BSE - 3299 ) | ( NSE - 13773 ) | ( MSEI - 73200 ) | ( MCX - 40585 ) | ( NCDEX - 01006 ). Depository Participant SEBI Reg. No. - IN - DP - 84 - 2015, DP ID CDSL - 12066900, NSDL ID - IN301895. Research Analyst - INH000000222 (CIN. NO.: U65999MH2010PTC198714)

Please note that the information shared is intended solely for informational purposes and does not make any investment recommendations