NIFTY expiry 8 September 2026: what the 23,650 options did in the last 30 minutes
On Tuesday 8 September 2026 the NIFTY strike nearest the index at 15:00 was 23,650. The index went from 23,641 at 15:00 to 23,635 at 15:30, down 6 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 |
|---|---|---|---|---|---|---|
| 23,650 CE | ₹41.8 | ₹53.9 15:10 | ₹0.1 15:29 | ₹0.1 | worthless | 28.8M → 33.5M |
| 23,650 PE | ₹33.4 | ₹90.8 15:21 | ₹12.2 15:17 | ₹14.9 | 0.4× | 30.9M → 16.2M |
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 23,650 call was ₹41.8 at 15:00. Its high was ₹53.9 at 15:10. Its low was ₹0.1 at 15:29, less than half of where it started the half hour. It ended at ₹0.1, worthless. Open interest at the strike went from 28.8 million to 33.5 million, so positions were added through the window.
The 23,650 put was ₹33.4 at 15:00. It reached ₹90.8 at 15:21, 2.7× its 15:00 price. Its low was ₹12.2 at 15:17, less than half of where it started the half hour. It ended at ₹14.9, 0.4× the 15:00 price. Open interest at the strike went from 30.9 million to 16.2 million, so positions were closed through the window.
Gamma Terrain's pin-book read flipped: at 15:16 the resting depth read the put strikes below the pin thinning (puts 26 %, calls 112 % of their baseline). A flip names the side whose book is emptying. Across 45 sessions it has not been a direction tell, it is a vacuum tell.
Chain quotes were missing 15:10–15:16: the exchange rate-limited the poll in the endgame, so the chart shows a hole there rather than a line. Highs and lows inside a hole are not known.
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.
Gamma Terrain shows the pin, the walls, the book read and every large print, tick by tick, on NIFTY and SENSEX.
The recap is the after-photo. The terrain is the window while it happens.
Read every panel behind these numbers, chapter by chapter.
Trading by the Numbers walks through the quantitative reads behind a modern F&O dashboard — order-flow imbalance, footprints, VWAP bands, OI flow, gamma structure and the expiry endgame — in plain trader-to-trader language.