In the last week of a series, charts in the F&O universe start behaving oddly. A stock closes 3% higher on a Tuesday with no announcement. Another grinds down all week and recovers most of it the following Monday. Volume spikes in the final half hour and collapses the next morning. None of this is the market re-pricing the business. It is several thousand positions being unwound or carried forward against a hard deadline, under margin rules that tighten by the day.
A wedding caterer books 400 kilos of rice from a mill months ahead. For most of that time the booking is paper — he can sell it on, swap it for a later date, or let it go. In the final few days the mill wants the balance payment and schedules a truck. Suddenly the arrangement stops being a piece of paper and becomes 400 kilos of rice arriving at a gate.
A stock futures or options position is paper right up until the last few sessions of the series. Then the delivery margin steps up, and at expiry the contract converts into actual shares moving between actual demat accounts against actual cash.
What physical settlement means
Every single-stock futures contract still open at expiry, and every single-stock option that finishes in the money, is settled by delivery of shares. It is not optional and there is no cash alternative; an option that finishes out of the money simply lapses. Index derivatives — Nifty, Bank Nifty and the rest — remain cash-settled, which is why the two behave so differently in the final week even though the charts look similar.
| Position held into expiry | What you must do | Cash involved |
|---|---|---|
| Long futures | Take delivery of the shares | Pay the full contract value |
| Short futures | Deliver the shares | Receive the full contract value |
| Long call, in the money | Take delivery | Pay the strike × lot size |
| Short call, in the money | Deliver the shares | Receive the strike × lot size |
| Long put, in the money | Deliver the shares | Receive the strike × lot size |
| Short put, in the money | Take delivery | Pay the strike × lot size |
The delivery margin ramp
Because the exchange cannot wait until expiry morning to find out who can fund delivery, additional margin is collected in steps over the final four sessions on positions likely to result in physical settlement. The percentages are set by exchange circular and have been revised more than once, but the shape has been stable: a small levy four days out, rising steeply to a large fraction of the settlement value on the eve of expiry.
| Session | Delivery margin levied | What it does to behaviour |
|---|---|---|
| Four days before expiry | A first, modest slice | The earliest wave of unwinding starts here |
| Three days before | Materially higher | Traders holding on borrowed capital begin to be squeezed out |
| Two days before | Higher again | Rollover activity peaks; near-month open interest falls sharply |
| The day before expiry | Most of the settlement value | Only participants who genuinely intend to take or give delivery remain |
| Expiry day | The full obligation crystallises | Pinning near large strikes; distorted final-hour volume |
Rollover percentage, and what it does and does not say
Rather than settle, most participants roll: close the near-month contract and open the same exposure in the next series. NSE publishes the resulting rollover percentage, which Indian market commentary quotes constantly and explains rarely.
- OI
- Open interest, measured in shares or contracts, at the end of expiry day
- Near month
- The series that is expiring
- Next and far month
- The two series that continue
Example: Near month 12 lakh shares, next month 34 lakh, far month 2 lakh: (34 + 2) ÷ 48 = 75%. Read against the stock’s own three-month average, not against 100%.
- Futures
- The price of the contract you are carrying into
- Spot
- The cash market price of the same stock
- Days to expiry
- Calendar days remaining in the series you are rolling into
Example: A positive number roughly in line with short-term interest rates is ordinary. A large positive number means people are paying up to stay long. A negative number — the future below spot — has two ordinary explanations before it has an interesting one: a dividend due before expiry, which the futures price discounts because a futures holder does not receive it, or enough selling pressure in the futures that shorts are willing to sell below the cash price. Check the ex-date first; only then is a discount evidence about positioning.
The squeeze that occasionally becomes real
- Elevated volume in the final half hour of expiry day
- Price gravitating towards a strike with very large open interest
- A move in the last two sessions that unwinds in the first two of the next series
- A widened basis while delivery margins are at their peak
- A stock with a small deliverable free float and a large short futures position
- Short interest that cannot be covered from available lendable stock
- Price rising into expiry on falling open interest, with no news of any kind
- A move that continues into the new series rather than reversing
Because shorts must actually produce shares, a stock where the deliverable float is small relative to the short position creates a genuine problem: covering requires buying in the cash market, and the buying itself moves the price. That is a real squeeze rather than a calendar artefact, and the tell is that it does not reverse when the new series begins.
You hold one lot of long call options on a stock, bought for ₹4,200 in premium, that will finish about 1% in the money at expiry. What happens if you do nothing?
Mahine ke aakhir mein kirayedaar ya toh agreement badhata hai ya saamaan uthata hai — aur us hafte gaadi, mazdoor, sab mehnge. Expiry week wahi hai: position roll hogi ya kategi, aur ab stock futures delivery se settle hote hain, isliye aakhir ke chaar din margin badhta jaata hai. Us hafte ke move ko company ki khabar mat samjho.
- Every stock derivative open at expiry settles in shares; index derivatives settle in cash.
- Delivery margins step up across the final four sessions, forcing unwinding on a fixed calendar.
- A small in-the-money option becomes a full contract-value obligation at expiry.
- Rollover percentage means little without the cost of carry beside it — it does not say which side rolled.
- Expiry-week moves that reverse in the new series were the calendar; ones that do not may be a real squeeze.
Mark it done to track your progress through the curriculum.
Common questions
Short, direct answers to what people ask about this topic.
- physical settlement in f&o meaning
- Physical settlement means a derivative contract is closed by actual delivery of shares rather than by a cash difference. Every single-stock futures position still open at expiry, and every single-stock option that finishes in the money, results in shares moving between demat accounts against the full cash consideration. Index derivatives such as Nifty and Bank Nifty remain cash-settled, which is why the two behave so differently in the final week.
- single stock derivatives left open at expiry in india are settled by
- Delivery of shares. Compulsory physical settlement of stock derivatives was phased in by SEBI and applied to the entire single-stock F&O universe from the October 2019 expiry, so there is no cash alternative and it is not optional. Options that finish out of the money simply lapse; everything else results in shares changing hands.
- what happens if I do not sell my in the money option before expiry
- It is exercised and physically settled, which means paying the strike price on the entire lot and taking delivery of the shares — an obligation that can be many times the premium paid. A call bought for a few thousand rupees that finishes marginally in the money still converts into a full contract-value commitment, and if you cannot fund it the broker closes the position at whatever the market gives or short-delivery consequences follow. Closing the option before expiry avoids the situation entirely, which is why almost everyone does.
- how is rollover percentage calculated
- Rollover % = (next month open interest + far month open interest) ÷ (near month + next month + far month open interest), measured at the end of expiry day. Near month 12 lakh shares, next month 34 lakh and far month 2 lakh gives (34 + 2) ÷ 48 = 75%. Read it against the stock’s own three-month average rather than against 100, and always beside the cost of carry — the percentage on its own does not say which side rolled.
- why is extra margin charged in expiry week
- Because the exchange collects delivery margin in steps over the final four sessions on positions likely to end in physical settlement, rather than waiting until expiry morning to discover who can fund delivery. It begins as a modest slice four days out and rises to most of the settlement value on the eve of expiry, so carrying a position through expiry week gets more expensive on a fixed calendar. That is why so many expiry-week moves reverse in the first sessions of the new series.