Lot size changes in index derivatives effective December 30, 2025

NSE has announced a revision in the market lot sizes for index derivative contracts, in line with SEBI’s periodic review guidelines. The revised lot sizes will be applicable from 28 October 2025 (end of day).

This revision is based on the average closing prices of the underlying indices for September 2025, to ensure that contract values remain within SEBI’s prescribed limits. The existing lot sizes will continue to apply for all weekly and monthly contracts until the 30 December 2025 expiry. From 30 December 2025 (end of day), the revised lot sizes will also apply to quarterly and half-yearly contracts.

Revised lots (effective from December 30, 2025)

The market lot of derivative contracts on the following Index is unchanged:

Which expiries will shift to the new lots?

Revision for quarterly and half-yearly contracts

Please note the following important updates on index derivative lot sizes:

• The revised lot sizes for NIFTY 50 and BANKNIFTY quarterly and half-yearly contracts will come into effect from 30 December 2025 (end of day).
• From 30 December 2025, fresh positions in quarterly and half-yearly contracts with the existing lot sizes will not be allowed.
• If you hold open positions with the existing lot sizes after 30 December 2025, you will not be able to square them off after the revision and will need to hold them until expiry.

For Long Positions (Option Buy)

For quarterly or half-yearly contracts expiring March 2026 or later, long positions must be exited by 30 December 2025. If not exited, these positions may become worthless.

For Short Positions (Option Sell)

Scenario 1: Positions in multiples of the revised lot size

If your existing short positions are in multiples of the revised lot size, you will be allowed to continue trading in these contracts.

Scenario 2: Positions not in multiples of the revised lot size

If your existing short positions are not in multiples of the revised lot size by 30 December 2025, we may square off such positions after 12:00 PM on 30 December 2025, on a best-effort basis. This is to avoid potential issues in squaring off these positions in the event of a margin shortfall after 30 December 2025.

For full details, refer to the exchange circular.