NSE F&O data for this week covers the full five session week, Monday 12 October through Friday 16 October 2026. Futures turnover across the week totalled INR 420,083.3 crores and options premium turnover totalled INR 405,463.2 crores. The Nifty 50 rose 2.24%, from 22,612.6 to 23,119.2, and the Bank Nifty rose 0.79%, from 55,479.6 to 55,918.0, both closing the week higher. Here is the detail, based on insights from bhavcopydata.com.
Futures, long buildup leads for the first time in weeks
We compared open interest and price in every stock futures contract from Friday 9 October, the last trading day before this week began, to Friday 16 October, keeping only contracts with at least INR 1 crore of turnover across the week. Of 619 qualifying stock futures contracts, 300 fell into long buildup against 176 in short buildup, with 105 in short covering and 38 in long unwinding. Unlike last week, when short buildup outnumbered long buildup even on a rising index, this week's positioning matched the market's direction, more stock futures built fresh bullish bets than bearish ones as both the Nifty 50 and the Bank Nifty closed higher.
A large share of the week's biggest open interest swings sat in contracts expiring in November and December rather than the near month, HDFC Bank Limited (HDFCBANK) alone added 164.1% to its December contract's open interest and 54.3% to its November contract, while its own October contract saw open interest fall 11.1% on the week's heaviest single stock futures turnover, INR 9,924.8 crores, as price rose 2.57%. Tata Steel Limited (TATASTEEL) showed the same split, open interest up 173.8% in its November contract against a 5.9% decline in October, and Suzlon Energy Limited (SUZLON) added 65.4% to November open interest against a 5.5% decline in October. Reading a single stock across more than one expiry at once like this is the main caveat with the buildup framework this week, the same name can show up bullish in one contract and bearish in another simply because fresh positioning is landing in the further out month rather than the one closest to expiry.
Within the long buildup group, Indian Railway Finance Corporation Limited (IRFC) stood out on direction rather than scale, its November contract rising 6.58% as open interest climbed 105.3% on INR 212.3 crores of turnover. In short buildup, Steel Authority of India Limited (SAIL) and IDFC First Bank Limited (IDFCFIRSTB) both saw open interest rise nearly thirteen fold in their November and December contracts respectively, as price fell a modest 1.47% and 1.72%, on turnover of INR 521.1 crores and INR 161.4 crores, moves large enough on real volume to treat as genuine fresh short positioning rather than a thin contract swinging on a small base. In long unwinding, Vodafone Idea Limited (IDEA) saw the week's single largest open interest decline across all stock futures in its October contract, down 159.9 million units, a 2.6% fall, even as its price fell a modest 2.92% on INR 1,475.0 crores of turnover, existing long positions exiting rather than fresh shorts being added.
The week's steepest single stock futures price fall by far was Yes Bank Limited (YESBANK). Its October contract traded in a tight band through Monday to Wednesday, between INR 20.42 and INR 21.17 on turnover of INR 158.0 crores to INR 301.5 crores a day, then fell 13.9% to INR 18.22 on Thursday 15 October alone, on turnover of INR 2,027.4 crores that day, roughly seven to thirteen times its turnover on any other day that week. The stock fell a further 3.3% on Friday to close the week at INR 17.61 on INR 471.2 crores of turnover, a cumulative weekly fall of 14.47% in the October contract. Its November and December contracts fell by a similar 14.4% to 14.6% over the same period as open interest rose sharply in both, landing them in short buildup rather than long unwinding, since the fall came alongside fresh short positioning rather than existing longs exiting. The size of the single day volume spike on Thursday points to a real, news driven move rather than a data artifact.
By turnover, the Nifty 50's October contract was the week's busiest at INR 40,517.2 crores, followed by the Bank Nifty's October contract at INR 14,220.7 crores. Away from the indices, HDFC Bank Limited (HDFCBANK) led all stock futures at INR 9,924.8 crores, followed by Reliance Industries Limited (RELIANCE) at INR 8,315.8 crores, ICICI Bank Limited (ICICIBANK) at INR 8,002.6 crores, Infosys Limited (INFY) at INR 7,984.8 crores and Tata Consultancy Services Limited (TCS) at INR 7,689.3 crores.
We checked whether this week's largest block and bulk deal net buyers also showed up building long futures positions in the same stock. None of the week's net buyers in block and bulk deals had a matching stock futures contract in the long buildup group this week, so there is no crossover signal to report this week.
Options, Bank Nifty's put call ratio climbs even as the index rises
The Bank Nifty's October monthly contract put call ratio by open interest opened the week at 0.90 on Monday, swung up to 1.07 on Tuesday, eased back to 0.98 on Wednesday, then rose again to 1.08 on Thursday before closing the week at 1.06 on Friday, even as the index itself gained 0.79%. The net move across the week was puts accumulating faster than calls, the same direction as last week's move but a noisier path and a smaller net swing. Nifty Financial Services (FINNIFTY) moved in a similar direction, its ratio rising from 0.55 on Monday to 1.00 on Thursday before easing to 0.89 on Friday. The Nifty 50's own ratio is harder to read cleanly this week, its nearest weekly contract rolled from the 13 October expiry to the 19 October expiry midweek, so the ratio seen on each side of that roll reflects two different contracts rather than one continuous reading, 1.40 on the 13 October contract's last day against 0.86 on the first day of the 19 October contract.
By Friday's close, the Nifty 50's 19 October contract showed the heaviest open interest at the 24,000 call strike, about 881 points above the week's close, and the 22,000 put strike, about 1,119 points below. The Bank Nifty's October contract showed the heaviest open interest at the 56,000 call strike, just 82 points above its own week's close, and the 55,000 put strike, 918 points below, a tighter call side ceiling than the Nifty 50's own options market is pricing.
Options premium turnover totalled INR 405,463.2 crores across the week. The Nifty 50's weekly contract expiring 13 October was the busiest on the site at INR 194,295.0 crores, and the contract expiring 19 October added a further INR 132,775.9 crores across the sessions it was active that week. The Nifty 50's own October monthly contract added INR 16,203.1 crores, and the Bank Nifty's October monthly contract added INR 14,192.2 crores. Away from the indices, Tata Consultancy Services Limited (TCS) options were the most active on any single stock at INR 1,700.6 crores, followed by Tech Mahindra Limited (TECHM) at INR 1,401.7 crores, Reliance Industries Limited (RELIANCE) at INR 1,289.1 crores, HCL Technologies Limited (HCLTECH) at INR 1,184.4 crores and Bharat Heavy Electricals Limited (BHEL) at INR 1,170.0 crores, a list leaning toward the same IT names that led the ETF market this week.
Track the full daily breakdown on the Futures and Options pages. More insights are on bhavcopydata.com.
All figures are from NSE end of day futures and options data for 12 to 16 October 2026, as published on bhavcopydata.com. See the Futures and Options pages for the full daily breakdown, and follow the author at @psanivarapu or prashanthsanivarapu for more.