SENSEX expiry 27 August 2026: what the 77,200 options did in the last 30 minutes
On Thursday 27 August 2026 the SENSEX strike nearest the index at 15:00 was 77,200. The index went from 77,245 at 15:00 to 76,934 at 15:30, down 311 points across the settle walk.
The at-the-money legs, 15:00 to 15:30
| Leg | 15:00 | High | Low | 15:30 | End vs 15:00 | Open interest |
|---|---|---|---|---|---|---|
| 77,200 CE | ₹135 | ₹167 15:00 | ₹0.1 15:30 | ₹0.1 | worthless | 4.6M → 6.5M |
| 77,200 PE | ₹43.1 | ₹448 15:27 | ₹34.0 15:00 | ₹266 | 6.2× | 8.6M → 2.1M |
Premium of the strike nearest the index at 15:00, sampled every ten seconds from the NSE option chain. Index values are the chain's own quote. Dotted verticals mark a pin-book flip on Gamma Terrain.
What happened
The 77,200 call was ₹135 at 15:00. Its high was ₹167 at 15:00. Its low was ₹0.1 at 15:30, less than half of where it started the half hour. It ended at ₹0.1, worthless. Open interest at the strike went from 4.6 million to 6.5 million, so positions were added through the window.
The 77,200 put was ₹43.1 at 15:00. It reached ₹448 at 15:27, 10× its 15:00 price. It ended at ₹266, 6.2× the 15:00 price. Open interest at the strike went from 8.6 million to 2.1 million, so positions were closed through the window.
For context, across 21 NIFTY and SENSEX expiries measured to 2026-09-08, 15 of 42 at-the-money legs doubled at some point in this window, 26 lost half, and 13 ended at or above their 15:00 price. This page states what the tape did. It is not a recommendation to buy or sell anything.
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