NSE reduces F&O lot sizes for Nifty 50 and three other indices from October 28

The last expiry with existing lot size for Nifty's weekly and monthly contract are on December 23, 2025, while the monthly Nifty and Bank Nifty contract will expire on December 30.

The National Stock Exchange (NSE) has revised the lot sizes, or the minimum shares that can be traded in one futures or options contract, with effect from October 28 for four major indices including Nifty 50, according to an official circular.

The Nifty 50 lot size has been reduced from 75 to 65, while the Nifty Bank lot size has come down from 35 to 30. Similarly, the Nifty Financial Services lot size has been revised from 65 to 60, and the Nifty Mid Select index lot size from 140 to 120.

The market lot of derivative contracts for the Nifty Next 50 Index remains unchanged.

Investors can continue to trade with the existing lot sizes until the December 30, 2025 expiry, after which all new contracts of any maturity will follow the revised, smaller lot sizes.

"Members are advised to inform their clients who have positions or take any new positions in the quarterly and half yearly contracts, of the upcoming revision in lot size on the below-mentioned dates," NSE said.

The last expiry with existing lot size for Nifty's weekly and monthly contract are on December 23, 2025, while the monthly Nifty and Bank Nifty contract will expire on December 30.

The NSE revises lot sizes of Futures & Options contracts primarily to keep the contract value within a standard range, to keep the contracts affordable and standardized. Since derivatives are leveraged instruments, traders do not have to pay the full value of the contract upfront, but the lot size determines their exposure and the margin required. The NSE undertakes lot size revisions to ensure market efficiency and liquidity, and to contracts more acceptable for a broader set of market participants.