An increase in foreign institutional participation has resulted in non-expiry day volumes on BSE to increase sharply from fiscal year 2024-25 (FY25) to FY26, market experts said, citing the Securities and Exchange Board of India’s (Sebi) recent study titled “profitability of individual traders in the equities derivatives segment FY25-FY26”.
The study, released earlier this month, examines both expiry and non-expiry average daily premium turnover over three periods—pre-policy tightening (April-October 2024), immediate post-policy (December 2024 -March 2025), and the recent period (October 2025-March 2026).
The regulatory tightening refers to tripling contract size, rationalizing weekly expiries to one per exchange from multiple earlier and doubling the tail risk margin (extreme investment outcome risk) on expiry day, among others. Additionally, the government raised the securities transaction tax (STT) on futures and options, too, in October 2024.
Regulatory curbs were rolled out in phases from November 2024 through March and December 2025 to tame the retail frenzy in options trading, leading to aggregate losses of ₹1.8 trillion among retail traders over three years (FY22-24).
Interestingly, the study found that BSE expiry day average daily turnover (ADT) jumped by 15.2% from ₹22,271 crore pre-policy to ₹25,648 crore in the immediate post-policy period.
The non-expiry day ADT surged 528.4% to ₹6,917 crore from ₹1,101 crore. To be sure, the incremental percentage looks inflated as it is on a very low base.
The expiry ADT of BSE stood at ₹53,357 crore in the recent period. The non-expiry day ADT rose further to ₹15,667 crore in the third period ending in FY26.
Consequently, the BSE expiry to non-expiry ratio decreased sharply from 20.2 times pre-policy to 3.7 times immediate post-policy and to 3.4 times in the third period under review.
In the case of the larger rival, NSE, the ratio remained the same at 1.1 times in the second period and increased to 1.6 times in the third period. This was because while the expiry day Nifty options ADT rose above the pre-policy average, the non-expiry ADT, while improving, stayed below the pre-policy average.
“The rise in non-expiry day ADT of Sensex options is attributable to greater institutional participation,” said Shai Coelho, founder of markets analytics platform Vtrender. “Institutions tend to hold positions from Monday through Thursday as opposed to retail traders whose trades are concentrated on the expiry day (Thursday) .”
Sebi data supports this view. The share of foreign portfolio investors (FPI) in BSE’s equity derivatives segment turnover jumped to 3.22% in FY26 from 1.95% in the preceding fiscal year. The share in open interest (carry-forward positions) grew to 9.09% from nil over the comparative period.
The comparative FPI figures, as a percentage of turnover on the NSE, were 6.96%, and open interest was 31.70% in FY26.
According to S.K. Joshi, consultant, Khambatta Securities, Sensex options ‘ popularity surged alongside that of Nifty options after the Sebi policy tightening reduced the zero-day to expiry options to two per week per exchange from five earlier—in addition to Nifty options, NSE ran Nifty Midcap Select weeklies every Monday, Finnifty options every Tuesday and Bank Nifty on Wednesday. BSE ran the Sensex options on Friday during the pre-policy period.
“Sebi cut that to just on a weekly basis per exchange effective November 2024, resulting in those volumes moving to the Nifty and Sensex, which gained traction over time,” explained Joshi.
Currently, Sensex options expire on Thursdays, while Nifty options expire on Tuesdays.
Consequently, non-expiry days for the Sensex include Friday, Monday, Tuesday, and Wednesday. For NSE, they include Wednesday, Thursday, Friday and Monday.
The rising popularity of Sensex options has led to a surge in the BSE-traded share price. The BSE share has risen 50.2% over one year to ₹3327.8 apiece against the Nifty Midcap 50’s absolute tourney of 14.7% , per NSE data. Over three years, BSE has returned 1005.21%, while the midcap index gained 66.73%.
The outperformance has catapulted BSE to the Nifty 50 index where it will replace Wipro effective 30 September.
