In an important action that will affect the trading dynamic in India’s derivatives market, in Futures & Options (F&O) contract the National Stock Exchange (NSE) and Bombay Stock Exchange (BSE) have officially announced changes for the weekly & monthly expiry days. This change comes after when market regulator, SEBI introduced a rule related to weekly & monthly expiry of index derivative only one of two days either Tuesday or Thursday. The NSE and BSE both had their contract expiring on the same day and it led to operational issues & high market volatility. After making this change, SEBI aim to make market work more smoothly, reduce the risk of too much pressure on single day and spread out trading activity across the week. This change makes a strategic shift in financial markets, mainly for BSE which had recently gained traction with its Tuesday expiries.

What Changed?

On June 17, 2025, both exchange NSE and BSE announced changes in their expiry day schedule. This decision comes into effect from 1 September, 2025 and it is according to the new framework of SEBI which bring uniformity and reduce risk in derivative market of India.

• NSE: From September 1, 2025, all weekly and monthly index derivative contracts will expire on Tuesday, including Nifty and Bank Nifty.
• BSE: From 1 September, 2025, all weekly and monthly derivative contracts will expire on Thursday, including Sensex and Bankex.

The current expiry structure will remain in place until the end of August 2025, means NSE contracts expiring on Thursday and BSE contracts expiring on Tuesday.

 Why This Was Needed?

In past, both NSE and BSE were allowed to decide any day for expiry in F&O contracts. This caused confusion and high volatility in market because both exchanges having expiry dates close to each other. In 2023, BSE started offering its weekly expiry on Tuesdays which was two days earlier from NSE regular Thursday expiry. It provided opportunity for trader to trade earlier in week and many shifted to BSE.

To solve the problem of both exchanges, related to expiry days & to reduce sudden sharp movements in the market. SEBI come with new rule, according to this each exchanges have only one day for weekly expiry either Tuesday or Thursday, not both. It help in reducing systematic risk from too many expiries, spreading out trading activity more efficiently across week and prevent exchanges from direct expiry-day competition.

What Else Is Changing?

• To control speculative trading, SEBI reduce the number of short-term contract which mean from 1 July, 2025, BSE will stop offering weekly index futures contract.
• All ongoing contract and Open interest which expiring after September 1, 2025, will shifted to new expiry days based on revised schedule.