The volume-weighted closing price, the auto-exercise rule, and what actually happens to your position at 3:30 PM IST.
NSE settles F&O on the volume-weighted average price (VWAP) of the last 30 minutes of trading on expiry day — 3:00 PM to 3:30 PM IST. This is the official closing price all in-the-money options auto-settle against.
Understanding this is critical because retail traders frequently get burned by the VWAP rule. The 'closing price' on your terminal at 3:30:01 PM is the settlement price — but it can differ meaningfully from where the underlying was trading at 3:25 PM if there was a late move.
Take every trade in the underlying between 3:00 PM and 3:30 PM IST. Compute the volume-weighted average price across those 30 minutes. That's the settlement price.
VWAP means trades with larger volume count more. A 100,000-share trade at 22,150 has 10x the weight of a 10,000-share trade at 22,200. So the settlement price is biased toward where the institutional volume actually traded, not the last printed tick.
This is published by NSE shortly after market close as the 'closing price' for the underlying. The same price is used to settle every ITM option for that expiry.
Every in-the-money option auto-exercises at expiry. If a 22,000 NIFTY call is ITM at settlement (NIFTY closed above 22,000), it gets exercised — the holder receives the intrinsic value as cash; the writer pays it.
Auto-exercise happens automatically — you don't have to do anything. There's no choice to 'let it expire' once it's ITM. This produces the most common retail F&O surprise: holding an ITM option to expiry and getting hit with full-notional STT.
OTM options simply expire worthless. Premium goes to zero; the writer keeps everything collected; the holder loses the premium paid.
Index options (NIFTY, BANK NIFTY, etc.): always cash settled. There's no underlying to deliver — you can't 'take delivery of NIFTY'. Intrinsic value is paid/collected in cash.
Stock options: were physically settled historically (you had to take delivery of the shares) but moved to cash settlement for most contracts in recent years. Check the contract specs for the specific stock.
Index futures: always cash settled.
Stock futures: physically settled — you have to take delivery of the shares (if long futures expiring ITM) or deliver them (if short). This is why many stock futures see heavy unwind in the final hour of expiry.
The settlement price is the VWAP of trades between 3:00 PM and 3:30 PM, not the closing tick. If most of that window's volume traded around 22,140-22,145, the VWAP comes in slightly below the closing tick. NSE publishes the official settlement price shortly after market close.
Intrinsic = 22,150 - 22,000 = 150 points. Payout = 150 × 25 (lot) = ₹3,750 per lot, minus STT. STT on auto-exercise = 0.125% × 22,150 × 25 = ₹693. Net credit: ₹3,057 per lot. Always run this math BEFORE deciding whether to close or hold ITM positions.
No — auto-exercise of ITM long options doesn't require margin. The clearinghouse credits or debits the intrinsic value directly to your account. The only way to avoid auto-exercise is to close the position before settlement.
If you're long a stock futures contract that expires ITM (basically all stock futures expire ITM since there's no strike), you'll receive delivery of shares equal to one lot. You need cash in your account for the full share value on T+1, not just the futures margin. Most brokers force-close stock futures the morning of expiry to prevent this surprise.
You'll deliver shares. If you don't have the shares, your broker will short-cover at market close, often at an unfavourable price. Worse, NSE can apply a 20% auction penalty if shares can't be sourced. Always close short stock futures before expiry.
No — same mechanism, same VWAP calculation, same auto-exercise rule. The only difference is the timing (BANK NIFTY weekly = Wednesday, NIFTY weekly = Thursday) and the lot size (15 vs 25).