SEBI's Revised Closing Auction Runs 3:30 to 3:40 pm, With Most Changes From 7 December

The Securities and Exchange Board of India (SEBI) has revised the closing auction session, the short window at the end of the trading day in which closing prices are set. A circular dated 15 October 2026 changes the auction's timings and the trading hours of derivatives, and it sets rules for orders that carry over into the auction. Most of the changes take effect on 7 December 2026.

SEBI first introduced the auction in a circular dated 16 January 2026, according to CA Club India. This article sets out the revised timetable, the order rules, the fallbacks used to set the reference price and the dates on which each change applies.

How the Review Came About

The revision followed a consultation paper that SEBI issued on 12 September 2026. Wealthstar reports that the regulator received more than 3,500 comments on the paper, with the deadline for comments set at 3 October 2026.

The paper offered two timing options. In the first, continuous trading would run until 3:30 pm, the auction from 3:31 pm to 3:40 pm, and derivatives trading until 3:45 pm. In the second, continuous trading would end at 3:15 pm, the auction would run from 3:15 pm to 3:25 pm, and derivatives trading would end at 3:30 pm. The paper also proposed changes to expiry settlement pricing, index value dissemination, limit order cancellations and iceberg orders.

The paper pointed to a rise in premium trading during the auction window. On expiry days, in benchmark index options on the National Stock Exchange (NSE), average premium trading per minute rose from 126.31 crore in the 3:00 pm to 3:30 pm period before the auction (February to July 2026 expiries) to 189.82 crore in the 3:20 pm to 3:30 pm period during the auction (3 August to 3 September 2026 expiries), according to figures in the paper as reported by Wealthstar.

On 3 October 2026, SEBI chairman Tuhin Kanta Pandey said a circular would follow soon and that the comments would be reviewed quickly, according to Wealthstar. Corplawupdates reports that the final framework took in market feedback that cited concentration and manipulation risks.

The Ten-Minute Auction Runs in Four Phases

The closing auction runs for 10 minutes, from 3:30 pm to 3:40 pm, every trading day, according to Corplawupdates.

The first phase, at 3:30 pm, lasts one minute. It is used to calculate the reference price and to move trading from continuous trading into the auction.

Order entry opens at 3:31 pm for both limit and market orders and ends at 3:36 pm, according to ThePrint, Upstox, TaxGuru and Corplawupdates.

From 3:36 pm, only limit orders are accepted until the auction closes. Corplawupdates reports that market orders cannot be modified or cancelled once this stage begins.

The auction ends with a random close between 3:38 pm and 3:40 pm, set by the system within that two-minute window.

Rules for Orders That Carry Over

Unexecuted limit orders from continuous trading move into the auction. Stop-loss orders and orders priced beyond the auction's price bands do not carry over, according to Outlook Business and Corplawupdates. Corplawupdates also reports that stop-loss orders are not allowed during the auction at all.

Iceberg orders cannot be placed during the auction itself. Those that move from continuous trading convert into fully disclosed limit orders within the applicable bands, unless the participant opts out, according to Outlook Business and Corplawupdates.

Orders moved from continuous trading receive higher time priority than new limit orders placed in the auction, according to TaxGuru and Corplawupdates. TaxGuru reports that the transition rules for these orders, set out in paragraph 4.8 of the circular, take effect on 8 February 2027.

Trading Hours Around the Auction

Index derivatives trade until 3:45 pm on all trading days. On expiry days, trading in expiring index derivatives contracts ends at 3:30 pm.

Stock derivatives trade until 3:45 pm every day, including expiry days.

After the auction, the cash segment has a post-close session from 3:50 pm to 4:00 pm, in which trades take place at the closing price, according to Upstox and Corplawupdates.

The circular also moves the settlement of expiring stock and index derivatives to a 30-minute volume-weighted average price, calculated over the last 30 minutes of continuous trading. That settlement change is separate from the auction timetable covered here.

From 3:36 pm, only limit orders are accepted until the auction closes.

Reference Price and Fallback Rules

The reference price used in the auction is the volume-weighted average price of trades in the last 15 minutes of continuous trading.

If no trades occur in that 15-minute window, the reference price falls back to the last traded price of the security during the day. If the security has not traded that day, the previous trading day's closing price is used, adjusted for corporate actions, according to TaxGuru and Corplawupdates.

Effective Dates and the Stated Aims

Most changes take effect on 7 December 2026. Corplawupdates lists the auction timings, the 30-minute VWAP settlement, margins, the reference price and the price bands among them.

The rules on carried-over orders apply from 8 February 2027.

According to ThePrint, SEBI's stated aims are better transparency and price discovery, and a more orderly closing process. ThePrint says SEBI proposed changes in September following concerns over the existing methodology.

For traders, the practical changes are the auction window, the expiry-day cut-off for index derivatives and the order restrictions from 3:36 pm.