F&O Expiry Day Explained: Settlement, Rollover and Risks

What expiry means

Each F&O contract has a last trading day, its expiry. After that day the contract stops trading and every open position is settled. Exchanges list weekly contracts for some indices and monthly contracts for others and for stocks. The exact weekdays are set by exchange rules and change from time to time, and when an expiry falls on a holiday it moves to the previous trading day.

Because expiry is fixed, options and futures are not things you can hold forever. Planning a trade means planning what happens at or before expiry.

How index contracts settle

Index futures and options in India are cash-settled. No shares change hands. On expiry, futures are closed at the final settlement price and the difference is paid in cash.

Index options that expire in the money are settled in cash at their intrinsic value: for a call, settlement price minus strike; for a put, strike minus settlement price, multiplied by the quantity. Options that expire out of the money are worth zero.

How stock contracts settle

Stock futures and in-the-money stock options held through expiry are physically settled. That means actual shares must be delivered or received. A long stock future held to expiry becomes a purchase of the shares; a short one becomes a sale. An ITM call held by a buyer leads to buying the shares at the strike; an ITM put leads to selling them.

Physical settlement can require large amounts of money or shares that a small account does not have, and brokers often square off such positions before expiry or ask for extra margin in the final days. Check your broker's policy well before expiry.

Why expiry days are volatile

Time value is almost zero, so option premiums react sharply to small price moves. Gamma is very high for strikes near the current price, which means an option can swing from almost worthless to valuable within minutes.

Option sellers adjust and hedge large positions during the day, and short covering near popular strikes can cause sudden moves. Volumes are high and spreads in far strikes can widen. All of this makes expiry days attractive to some traders and dangerous for unprepared ones.

Rollover

To keep a futures position beyond expiry, traders roll over: they close the expiring contract and open the same position in the next one. The price difference between the two months is the rollover cost. Rollover data (how many positions moved to the next month) is watched as a rough sign of how many traders want to keep their views.

Options are usually not rolled in the same way; traders close the expiring option and, if they still want exposure, buy or sell a new one with a later expiry.

Common expiry-day mistakes

Holding a short option into the last hour because it "looks safe", only for a sudden move to turn a small credit into a large loss.

Buying lottery-ticket OTM options because they cost a few rupees, without noticing that the total spent across many attempts adds up.

Forgetting a stock F&O position until the broker squares it off or physical settlement kicks in.

Trading far strikes with wide bid-ask spreads, where the cost of getting in and out eats the expected gain.

Ignoring charges: on expiry day, many small trades can mean many sets of brokerage and fees.

Planning around expiry

Know the expiry dates for anything you trade, and mark them on a calendar along with major events.

Avoid buying cheap far OTM options on expiry day hoping for a miracle; most expire worthless.

If you sell options, size positions so a sharp move near a strike does not cause an unacceptable loss, and use stop-losses or hedges.

For stock F&O, close or roll positions before the final days if you cannot handle physical settlement.

A worked example: settling an index option

Suppose you hold one lot (75) of a 24,000 call bought at ₹60, and the index's final settlement price on expiry is 24,130. The call is in the money by 130 points, so it settles at 130 x 75 = ₹9,750. Your profit is (130 - 60) x 75 = ₹5,250 before charges.

If the settlement price had been 23,990, the call would expire worthless and the full ₹4,500 premium would be lost. A difference of 140 points in the last hour decided the whole outcome, which is typical of expiry-day risk.

Expiry on iTradeChart

The market calendar lists upcoming expiries for each index and for stock F&O, along with results, holidays and RBI policy dates, and can remind you on the day. In paper trading, expired options and futures are settled automatically at the last price, so you can see the outcome of holding to expiry without real money.

After 3:30 PM on expiry day, expired contracts no longer appear in search or the option chain, so you do not accidentally trade a contract that has already ended.