NIFTY expiry 22 September 2026: what the 23,350 options did in the last 30 minutes
On Tuesday 22 September 2026 the NIFTY strike nearest the index at 15:00 was 23,350. The index went from 23,359 at 15:00 to 23,329 at 15:30, down 30 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 |
|---|---|---|---|---|---|---|
| 23,350 CE | ₹38.4 | ₹45.0 15:11 | ₹0.1 15:28 | ₹0.1 | worthless | 15.1M → 26.3M |
| 23,350 PE | ₹31.2 | ₹40.6 15:20 | ₹10.3 15:26 | ₹20.9 | 0.7× | 24.1M → 18.1M |
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 23,350 call was ₹38.4 at 15:00. Its high was ₹45.0 at 15:11. Its low was ₹0.1 at 15:28, less than half of where it started the half hour. It ended at ₹0.1, worthless. Open interest at the strike went from 15.1 million to 26.3 million, so positions were added through the window.
The 23,350 put was ₹31.2 at 15:00. Its high was ₹40.6 at 15:20. Its low was ₹10.3 at 15:26, less than half of where it started the half hour. It ended at ₹20.9, 0.7× the 15:00 price. Open interest at the strike went from 24.1 million to 18.1 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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