SEBI revamps F&O trading hours from 3 August, closes at 3:40 PM
Synopsis
SEBI is overhauling how India's equity markets close. From 3 August, F&O-eligible stocks will have their closing prices set through a structured auction rather than a simple last-trade snapshot — a shift that aligns India with global exchanges and has real consequences for index funds, passive investors, and anyone trading near the close.
Key Takeaways
SEBI implements a revised equity trading framework from 3 August 2025 .
A Closing Auction Session (CAS) is introduced for F&O-eligible (Category I) stocks, running from 3:20 pm to 3:35 pm .
The auction-determined price will be the official closing price for all F&O-eligible stocks.
F&O segment trading hours are extended by 10 minutes , now closing at 3:40 pm .
Non-F&O equity cash stocks continue to close at 3:30 pm — no change.
Pre-open order entry window revised to 9:00 am – 9:07 am , with matching from 9:07 am to 9:15 am .
The Securities and Exchange Board of India (SEBI) will implement a revised equity market trading framework from Monday, 3 August, introducing a Closing Auction Session (CAS) for Futures and Options (F&O)-eligible stocks and extending derivatives trading by 10 minutes to 3:40 pm. The changes are aimed at strengthening price discovery, improving market efficiency, and aligning India's equity market structure with global standards.
What the Closing Auction Session Means
Under the new framework, regular trading for F&O-eligible (Category I) stocks in the equity cash segment will continue until 3:15 pm, followed by a transition period running to 3:20 pm. The Closing Auction Session then begins with a first order entry window from 3:20 pm to 3:25 pm.
A second order entry phase runs from 3:25 pm to 3:30 pm, during which investors will not be permitted to modify or cancel market orders. The auction will conclude at a random point within the final two minutes of this phase. Order matching will take place between 3:30 pm and 3:35 pm, after which the auction price is determined. The price discovered through this session will serve as the official closing price for all F&O-eligible stocks.
Extended F&O Segment Hours
SEBI has extended trading hours in the equity derivatives segment by 10 minutes. Trading in the F&O segment will now run until 3:40 pm, up from the previous close. Timings for all other market segments remain unchanged. Non-F&O equity cash stocks will continue to close at 3:30 pm as before.
Pre-Open Session Changes
The regulator has also revised the pre-open session schedule. The order entry window will now remain open from 9:00 am to 9:07 am, followed by order matching from 9:07 am to 9:15 am. The regular trading session will continue to begin at 9:15 am.
Why SEBI Is Making These Changes
According to SEBI, the Closing Auction Session is designed to aggregate liquidity through an auction-based process, improving the quality of closing prices. The regulator stated the framework will provide equal access to all investors, reduce tracking errors for passive investment funds — a growing concern as index funds and ETFs proliferate in India — and bring domestic equity market practices closer to global benchmarks. Notably, major exchanges such as the London Stock Exchange and NYSE have long used closing auction mechanisms, making this a structural alignment move for Indian markets.
With passive investing gaining traction in India and index-tracking funds sensitive to end-of-day price accuracy, the shift is expected to have tangible benefits for institutional and retail investors alike. All market participants are advised to update their trading systems and strategies ahead of the 3 August rollout.
Point of View
Index rebalancing prices, and NAVs for passive funds. A last-trade-based close is vulnerable to end-of-day price manipulation; an auction-based close is significantly harder to game. India's passive fund industry has grown sharply, making accurate closing prices a systemic concern, not just a market-microstructure footnote. The real question is implementation: brokers, algo systems, and institutional desks will need to recalibrate, and the first few sessions will test whether the auction attracts sufficient liquidity to genuinely improve price quality or merely adds procedural complexity.
NationPress
2 Aug 2026
Frequently Asked Questions
What is the Closing Auction Session introduced by SEBI?
The Closing Auction Session (CAS) is a structured end-of-day auction mechanism for F&O-eligible stocks in the equity cash segment, effective from 3 August 2025. It runs from 3:20 pm to 3:35 pm, and the price discovered through this auction becomes the official closing price for all F&O-eligible stocks.
Why has SEBI extended F&O trading hours to 3:40 pm?
SEBI has extended equity derivatives (F&O) trading by 10 minutes to 3:40 pm to align with the new Closing Auction Session timeline and improve market efficiency. The regulator stated the move is part of a broader effort to bring India's market structure in line with global standards.
Which stocks are affected by the new Closing Auction Session?
Only F&O-eligible (Category I) stocks in the equity cash segment are covered by the new Closing Auction Session. Non-F&O equity cash stocks are unaffected and will continue to close at 3:30 pm.
Can investors modify or cancel orders during the Closing Auction Session?
Investors can enter and modify orders during the first order entry phase (3:20 pm to 3:25 pm). However, during the second phase (3:25 pm to 3:30 pm), modification or cancellation of market orders is not permitted. The auction concludes randomly within the final two minutes of this phase.
What changes has SEBI made to the pre-open session?
Under the revised framework, the pre-open order entry window runs from 9:00 am to 9:07 am, followed by order matching from 9:07 am to 9:15 am. The regular trading session continues to begin at 9:15 am — the start time is unchanged.
