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NISM Series V-D · Chapter 16: Introduction to Options

L1 · Foundation

Foundation — Calls, puts, moneyness and the four payoffs

What an option is and why it exists, the full vocabulary from writer to assignment, contract specifications for Nifty and Sensex options, in-the-money, at-the-money and out-of-the-money, intrinsic and time value, and the four payoff profiles worked through the chapter's own tables.

17 min read · Worth 9% of the paper · Written from pages 364–389 of the official NISM workbook · Updated 18 September 2026

16.1 Why options exist

"forward/futures contract is a COMMITMENT to buy/sell the underlying and has a **LINEAR payoff, which indicates UNLIMITED LOSSES AND PROFITS. However, some market participants desire to RIDE THE UPSIDE BUT RESTRICT THE DOWNSIDE. Accordingly, options have emerged as a financial instrument, as they allow UNLIMITED PROFITS on buying or selling of the underlying asset WITH A PROVISION OF RESTRICTING THE LOSSES."

"An option is a contract that gives the holder of the option THE RIGHT, BUT NOT AN OBLIGATION, to buy or sell the underlying asset ON OR BEFORE A STATED DATE/DAY, AT A PREDETERMINED PRICE. This right can be bought for a price known as the OPTION PREMIUM."

"The party taking a LONG position i.e., BUYING the option is called BUYER/HOLDER and the party taking a SHORT position i.e., SELLING the option is called the SELLER/WRITER. THE OPTION BUYER MUST PAY THE PREMIUM TO THE OPTION SELLER UPFRONT, i.e., AT THE TIME OF BUYING THE OPTION."

The asymmetry that defines the instrument: "the option buyer or holder has the RIGHT BUT NO OBLIGATION..., while the option writer HAS THE OBLIGATION... Therefore, the option buyer will EXERCISE HIS OPTION ONLY WHEN THE SITUATION IS FAVOURABLE TO HIM. On the other hand, the option writer is LEGALLY BOUND TO HONOUR THE CONTRACT WHENEVER THE OPTION BUYER DECIDES TO EXERCISE."

"An option, which gives the buyer/holder a RIGHT TO BUY the underlying asset, is called a CALL OPTION; and an option which gives the buyer/holder a RIGHT TO SELL the underlying asset, is called a PUT OPTION."

Option terminology

The chapter's two quotes as on 10 May 20XX, both with strike 18400, expiry 25 May 20XX, and underlying value 18315.10:

Call (European)Put (European)
Close price124.50177.60
Traded volume61,330 contracts31,388 contracts
Open interest14,97,6504,97,950
  • Index option — "These options have a STOCK INDEX as the underlying asset. For example, options on Nifty, Sensex."
  • Stock option — "These options have INDIVIDUAL STOCKS as the underlying. For example, option on ONGC, NTPC."
  • Buyer — "one who has a RIGHT BUT NOT THE OBLIGATION... he pays a price called 'option premium'... He has a right to BUY the underlying asset in case of a CALL option and the right to SELL the underlying asset in case of a PUT option."
  • Writer — "one who RECEIVES the option premium and is thereby OBLIGED to sell/buy the asset if the buyer exercises his right. He has a SELL obligation in case of a CALL option and a BUY obligation in case of a PUT option."
  • American option — "can exercise his right AT ANY TIME ON OR BEFORE the expiry date/day."
  • European option — "can exercise his right ONLY ON THE EXPIRY DATE/DAY of the contract. IN INDIA, ALL INDEX AND STOCK OPTIONS ARE EUROPEAN STYLE OPTIONS."
  • Option premium — "the price which the option BUYER PAYS to the option SELLER... The premium mentioned here is for a SINGLE UNIT and to arrive at the TOTAL premium for the contract, we must MULTIPLY THIS PREMIUM WITH THE LOT SIZE."
  • Spot price (S) — "the price at which the underlying asset is trading in the spot market."
  • Strike price or Exercise price (X) — "the price per share for which the underlying security may be PURCHASED by the CALL option holder (or SOLD by the PUT option holder)."
  • Exercise of options — "Option contracts traded on Indian exchanges are European style... buyers can exercise their options only at the time of MATURITY... All these options are exercised with respect to the SETTLEMENT VALUE/CLOSING PRICE of the stock on the day of exercise."
  • Assignment of options — "the ALLOCATION OF EXERCISED OPTIONS TO ONE OR MORE OPTION SELLERS."

Opening and closing. An opening transaction "ADDS TO OR CREATES a new trading position" — an opening purchase is going long, an opening sale is going short. A closing transaction "REDUCES OR ELIMINATES an existing position by an appropriate OFFSETTING purchase or sale", also called "squaring off": a closing purchase reduces a short position ("frequently referred to as covering"), a closing sale reduces a long position.

And a warning worth underlining: "A trader does NOT close out a LONG CALL position by PURCHASING A PUT (or any other similar transaction). A closing transaction for an option involves the sale or purchase of an option contract WITH THE SAME TERMS, i.e., an option with the SAME STRIKE PRICE AND SAME EXPIRY DATE."

16.2 Contract specifications

"the exchange decides all terms and conditions (EXCEPT THE OPTION PREMIUM) for all exchange-traded index and stock options."

Contract size. "the number of units of the underlying asset in a contract... different for option contracts on different stocks and indices." With a Nifty lot of 50, the total premium is 124.50 × 50 = Rs 6,225 for the call and 177.60 × 50 = Rs 8,880 for the put.

Contract trading cycle. "Index options in India are available for a WIDER RANGE of expiration dates as compared to STOCK options. Option contracts on INDIVIDUAL STOCKS traded on the NSE follow a THREE-MONTH trading cycle."

For index options: "available for trading with WEEKLY AS WELL AS MONTHLY maturities. Index options can be traded for 4 SERIAL WEEKLY CYCLES, excluding the monthly near-, mid- and far-month expiries... Index options are also available for THREE QUARTERLY EXPIRIES (March, June, September and December cycle). The exchanges also make available LONG-TERM index options having 8 HALF-YEARLY EXPIRIES (following the June-December cycle) after the three quarterly expiries."

Expiration date. "The Nifty and Bank Nifty option contracts expire on the LAST TUESDAY of the expiry month (or, on the PREVIOUS TRADING DAY, if the last Tuesday is a trading holiday)." And the recent restriction: "As per recent SEBI Circular dated Oct 01, 2024, exchanges may provide derivatives contracts for ONLY ONE OF ITS BENCHMARK INDICES WITH WEEKLY EXPIRY. This will be effective from NOV 20, 2024. For ex. BSE can only offer weekly Index derivative contract EITHER on Sensex 30 OR Bankex."

Tick size. "the tick size for index contracts is 5 PAISA." For stocks: "NSE: The tick size for stocks trading BELOW ₹250 is 0.01 paisa and for stocks trading ABOVE ₹250 is 0.05 paisa... BSE: The usual tick size is 0.05 paisa but tick size is 0.01 for stocks trading BELOW ₹100." And why it matters: "A SMALL tick size allows for BETTER RISK MANAGEMENT because positions can be adjusted with small price movements. A LARGE tick size may require HIGHER MARGINS due to the potential for larger price fluctuations."

Final settlement price. "Unlike the futures contracts, THERE IS NO DAILY SETTLEMENT OF OPTIONS CONTRACTS. Also, since all exchange-traded index and stock options in India are European style, the exercise and assignment... is permitted ONLY ON THE EXPIRATION DATE. The final settlement price... is the CLOSING PRICE OF THE RELEVANT INDEX OR STOCK IN THE CASH SEGMENT on the last trading day."

Trading hours. "between 9.15 am and 3.30 pm from Monday to Friday."

BSE Sensex options

SpecificationValue
UnderlyingBSE Sensex
Contract size20
Tick sizeRs 0.05
Contract cycle7 serial weekly, 3 monthly, 3 quarterly and 8 semi-annually maturing contracts
Trading hours9:15 a.m. to 3:30 p.m.
Exercise styleEuropean
Expiration dayMonthly, quarterly and semi-annually: last Thursday; weekly: Thursday
Final settlementCash settlement on the closing price of the underlying index on expiry

16.3 Moneyness

CategoryDefinitionCallPut
In-the-money (ITM)"would give the option holder a POSITIVE CASH FLOW, if it were exercised immediately"Spot HIGHER than strikeSpot LOWER than strike
At-the-money (ATM)"would lead to ZERO cash flow if it were exercised immediately" — in practice, "an option with a strike price which is CLOSEST to the spot price"Strike = spotStrike = spot
Out-of-the-money (OTM)"one with a strike price WORSE than the spot price for the holder... would give the holder a NEGATIVE cash flow if exercised immediately"Spot LOWER than strikeSpot HIGHER than strike

The ATM practicality: "because the strike prices are at FIXED INTERVALS of say, Rs 5, Rs 10 or Rs 50, while the spot price moves in MUCH SMALLER INCREMENTS, the two prices MAY RARELY BE EQUAL." The illustration: "if the index is at 18415 and three options... with strike prices of 18350, 18400 and 18450 are available, the option with the strike price of 18400 is an ATM option."

In the chapter's own quotes, with spot 18315.10 and strike 18400: "the PUT option is IN-THE-MONEY" and "the CALL option is OUT-OF-THE-MONEY."

16.4 Intrinsic value and time value

"The option premium... consists of TWO COMPONENTS - INTRINSIC VALUE and TIME VALUE."

"The INTRINSIC VALUE of an option refers to the amount by which the option is IN-THE-MONEY i.e., the amount an option buyer will realize, BEFORE ADJUSTING FOR PREMIUM PAID, if he exercises the option instantly. Therefore, ONLY IN-THE-MONEY OPTIONS HAVE INTRINSIC VALUE whereas at-the-money and out-of-the-money options have ZERO intrinsic value. THE INTRINSIC VALUE OF AN OPTION CAN NEVER BE NEGATIVE because an option holder is NOT BOUND TO EXERCISE an option if such exercise will result in a loss to him."

The chapter's figures: the put has an intrinsic value of 18400 − 18315.10 = Rs 84.90; the call has an intrinsic value of zero.

"TIME VALUE: It is the DIFFERENCE BETWEEN THE PREMIUM AND INTRINSIC VALUE, if any, of an option. ATM AND OTM OPTIONS HAVE ONLY TIME VALUE because the intrinsic value of such options is zero." So the put's time value is 177.60 − 84.90 = Rs 92.70, and "in the case of the call option, the ENTIRE option premium of Rs 124.50 represents TIME VALUE."

16.5 The four payoffs

Long option. "You have the RIGHT to exercise that option"; "Your potential loss is LIMITED TO THE PREMIUM AMOUNT you paid"; "Profit would depend on the LEVEL OF UNDERLYING ASSET PRICE at the time of exercise/expiry."

Short option. "Your MAXIMUM PROFIT is the PREMIUM RECEIVED"; "You can be ASSIGNED an exercised option any time during the life of option contract (in case of AMERICAN options). All option writers should be aware that ASSIGNMENT IS A DISTINCT POSSIBILITY"; "Your potential loss is THEORETICALLY UNLIMITED."

Long call — strike 17500, premium 95, index at 17562

"If the index closes at 17400, you will NOT exercise... Why will you buy something at 17500 when you can have the same thing at 17400?... your loss will be equal to the premium."

"If the index were to close at 17595, the option will expire in-the-money... you will receive a payoff of Rs 95... but you have already paid an equal amount..., making your net gain equal to ZERO. Hence, 17595 is the BREAK-EVEN POINT (BEP)... A general formula for calculating BEP for CALL options is STRIKE PRICE PLUS PREMIUM (X + P)."

At 18000: "you will receive a payoff of Rs 500... But since you have already paid Rs 95..., your actual profit would be Rs 500 – Rs 95 = Rs 405."

Index at expiry17100172001730017400175001760017700178001790018000
Premium paid−95−95−95−95−95−95−95−95−95−95
Payoff on expiry00000100200300400500
Profit−95−95−95−95−95+5+105+205+305+405

"The contract value for an index option with lot size of 50 and strike of 17500 is Rs 8,75,000. The MAXIMUM LOSS for such an option buyer would be equal to Rs 95 × 50 = Rs 4,750... A long call position helps you to LIMIT YOUR LOSS to a maximum of Rs 4,750 WITH POTENTIALLY UNLIMITED PROFIT."

And on margin: "As a call option buyer, you NEED NOT PAY ANY MARGIN to the Exchange because your PAYMENT OBLIGATION IS RESTRICTED TO THE OPTION PREMIUM that you have already paid."

Short call — the mirror image

"if the maximum loss for a long call position is equal to the premium paid, it automatically means that the MAXIMUM GAIN FOR THE SHORT CALL POSITION WILL BE EQUAL TO THE PREMIUM RECEIVED. Similarly, if maximum gain for long call position is unlimited, then the MAXIMUM LOSS FOR THE SHORT CALL POSITION MUST BE UNLIMITED."

Index at expiry17100175001760017700178001790018000
Short call profit+95+95−5−105−205−305−405

"BEP for a short call position will ALSO be equal to X + P. BEP IS INDEPENDENT OF POSITION (LONG OR SHORT), IT IS INSTRUMENT SPECIFIC (CALL OPTION)."

And the margin asymmetry: "Although the call seller receives a premium initially..., HE MUST PAY A MARGIN to the Exchange on the short position. This is because the option seller HAS AN OBLIGATION and since his LOSSES CAN BE UNLIMITED, HE CAN BE A POTENTIAL RISK FOR THE STABILITY OF THE SYSTEM."

Long put — strike 17500, premium 150

"You hold the right to SELL the index at 17500... You will do so ONLY WHEN THE INDEX IS AT A LEVEL LOWER THAN THE STRIKE PRICE... The maximum loss... will be equal to the premium already paid i.e., Rs 150."

"What can be the maximum profit? Theoretically, THE INDEX CAN FALL ONLY TILL ZERO. So, the maximum profit will be achieved when the index closes at zero... The profit in this case will be Rs 17,500, but since you have already paid Rs 150..., your net profit will be Rs 17,350."

Index at expiry17100172001730017400175001760017900
Long put profit+250+150+50−50−150−150−150

"A margin is paid ONLY IF THERE IS ANY OBLIGATION. An option buyer (either buyer of a call option or a put option) HAS NO OBLIGATION."

Short put

Index at expiry171001720017300174001750017900
Short put profit−250−150−50+50+150+150

"the gain of the put seller is FIXED at Rs 150, the premium received initially. However, the short put position starts making losses as the index dips below 17350, which is the break-even point. The seller of the put option receives the premium but HE IS REQUIRED TO PAY A MARGIN on his position as he has an OBLIGATION to deliver the underlying asset and HIS LOSSES CAN BE HUGE."

The risk and return table

RiskReturn
LongPremium paidUnlimited
ShortUnlimitedPremium received

Think of it like this

The token you can walk away from

An option exists because "some market participants desire to RIDE THE UPSIDE BUT RESTRICT THE DOWNSIDE." Pay a token to reserve a flat: if prices rise you complete the purchase and gain; if they fall you forfeit only the token. That is exactly the long call — "your potential loss is limited to the premium amount you paid", while "profit would depend on the level of underlying asset price." The builder, meanwhile, cannot walk away: "the option writer is LEGALLY BOUND TO HONOUR THE CONTRACT WHENEVER THE OPTION BUYER DECIDES TO EXERCISE." One side has a right; the other has only an obligation — and is paid a premium for accepting it.

Why buyers post no margin and writers must

The rule is beautifully simple: "A margin is paid ONLY IF THERE IS ANY OBLIGATION. An option buyer (either buyer of a call option or a put option) HAS NO OBLIGATION." The buyer has already paid everything he can ever lose — "your payment obligation is restricted to the option premium that you have already paid" — so he poses no further risk to anyone. The writer is the opposite: "he must pay a margin... because the option seller HAS AN OBLIGATION and since his losses can be unlimited, HE CAN BE A POTENTIAL RISK FOR THE STABILITY OF THE SYSTEM." Contrast futures, where both sides post margin because both are obliged.

Intrinsic value never goes below zero

Intrinsic value is S − X for a call and X − S for a put, "with a minimum possible value of ZERO." The reason is not a convention but a fact about rights: "the intrinsic value of an option CAN NEVER BE NEGATIVE because an option holder is NOT BOUND TO EXERCISE an option if such exercise will result in a loss to him." Nobody with an umbrella is forced to open it in the sun. So a call struck at 17500 with the index at 17400 has intrinsic value zero, not −100 — because the holder simply declines: "Why will you buy something at 17500 when you can have the same thing at 17400?"

Every premium is two things at once

Take the chapter's put: premium Rs 177.60, strike 18400, spot 18315.10. Split it. Intrinsic value = 18400 − 18315.10 = Rs 84.90 — the money you would get by exercising this instant. Time value = 177.60 − 84.90 = Rs 92.70 — what you pay for everything that might still happen. The companion call, being out of the money, has zero intrinsic value, so "the ENTIRE option premium of Rs 124.50 represents TIME VALUE." Learn to split any premium into these two parts and most of this chapter becomes arithmetic.

The break-even belongs to the instrument, not the position

A subtle line that examiners love: "BEP for a short call position will ALSO be equal to X + P. BEP IS INDEPENDENT OF POSITION (LONG OR SHORT), IT IS INSTRUMENT SPECIFIC (CALL OPTION)." A call struck at 17500 with a premium of 95 breaks even at 17595 for both parties — above it the buyer gains and the seller loses, below it the reverse. The same applies to puts at X − P, or 17350 in the chapter's example. The line in the sand is drawn by the contract, not by which side of it you happen to stand.

A put can only be so profitable

The long call has "potentially unlimited profit" because a price can rise without bound. The long put cannot: "Theoretically, THE INDEX CAN FALL ONLY TILL ZERO. So, the maximum profit will be achieved when the index closes at zero... The profit in this case will be Rs 17,500, but since you have already paid Rs 150..., your net profit will be Rs 17,350." Prices have a floor but no ceiling, which is why put profits are large-but-bounded while call profits are genuinely unlimited — and, correspondingly, why a short call is the most dangerous of the four positions.

In India, only on the last day

The distinction is easy to state and easy to forget. An American option "can exercise his right AT ANY TIME ON OR BEFORE the expiry date"; a European option "can exercise his right ONLY ON THE EXPIRY DATE/DAY." And then the fact that settles most Indian exam questions: "IN INDIA, ALL INDEX AND STOCK OPTIONS ARE EUROPEAN STYLE OPTIONS." Sample Question 4 is built on this — any statement that an Indian option may be exercised "on or before" expiry is false. Note the companion detail: there is no daily settlement for options, unlike futures.

Closing means the same contract, not the opposite one

A trap for beginners, and the chapter flags it explicitly: "A trader does NOT close out a LONG CALL position by PURCHASING A PUT (or any other similar transaction). A closing transaction for an option involves the sale or purchase of an option contract WITH THE SAME TERMS, i.e., an option with the SAME STRIKE PRICE AND SAME EXPIRY DATE." Buying a put alongside a long call does not cancel anything — it creates a second position with its own premium and its own risk. To close a long call you sell that same call; to close a short call you buy it back, which is "frequently referred to as covering."

Key terms in this chapter

American and European options
An American option may be exercised at any time on or before expiry; a European option only on the expiry day. In India all index and stock options are European style.
Assignment
The allocation of exercised options to one or more option sellers.
Asymmetric payoff
The feature that makes options different from futures — gains when the underlying moves one way differ significantly from losses when it moves the other. Futures payoffs are symmetric.
At-the-money (ATM)
An option that would give zero cash flow on immediate exercise. In practice, since strikes are at fixed intervals while spot moves in smaller increments, it is the strike closest to the spot price.
Binomial Pricing Model
Developed by William Sharpe in 1978, it maps the underlying's price evolution as a tree of possible prices at equally spaced time steps, with the price moving up or down at fixed rates and simulated probabilities. Very accurate because iterative, but complex and time consuming.
Black & Scholes Model
Published in 1973 by Fisher Black and Myron Scholes — popular, simple and fast, and unlike the binomial model it does not rely on iteration. It computes a theoretical call price from stock price, strike, volatility, time to expiration and the risk-free rate, ignoring dividends paid during the option's life.
Break-even point
Strike plus premium for a call and strike minus premium for a put. It is independent of whether one is long or short — it belongs to the instrument, not the position.
Call option and put option
A call gives the buyer the right to BUY the underlying; a put gives the buyer the right to SELL it. Correspondingly the writer of a call has a sell obligation and the writer of a put a buy obligation.
Closing transaction
A purchase or sale that reduces or eliminates an existing position — also called squaring off. It must involve an option with the same strike price and the same expiry date; buying a put does not close a long call.
Delta
The sensitivity of the option value to a small change in the underlying price — the speed at which the option moves with the underlying. Positive for a call buyer, negative for a put buyer, with the writer taking the opposite sign.
Gamma
The change in delta for a unit change in the underlying price — the second derivative, acting as the acceleration of delta and signalling how fast an option will move into or out of the money.
Historical volatility
Volatility measured by the standard deviation of percentage price changes in the underlying over a past period — a backward-looking figure.
Implied volatility
The volatility derived by running the Black-Scholes model in reverse from the observed option price, since every other input is known. It reflects expected volatility over the remaining life of the option rather than past price movement.
In-the-money (ITM)
An option that would give the holder a positive cash flow if exercised immediately — a call whose spot is above the strike, or a put whose spot is below it. Only ITM options have intrinsic value.
Intrinsic value
The amount by which an option is in the money — S − X for a call and X − S for a put, with a floor of zero, since the holder is never bound to exercise at a loss.
Leverage in options
Paying a relatively small premium for exposure to a much larger contract value. It magnifies percentage gains on favourable moves and percentage losses on adverse ones — and if the option expires worthless the entire premium is lost.
Option
A contract giving the holder the right, but not the obligation, to buy or sell the underlying on or before a stated day at a predetermined price, bought for a price called the option premium.
Option writer
The seller, who receives the premium and is obliged to buy or sell if the buyer exercises. He has an obligation and no right, which is why he must post margin and faces daily mark to market.
Out-of-the-money (OTM)
An option with a strike worse than the spot price for the holder, giving a negative cash flow on immediate exercise — a call whose spot is below the strike, or a put whose spot is above it. Its premium is entirely time value.
Rho
The change in option price for a one percentage point change in the risk-free interest rate — the sensitivity to the cost of funding the underlying.
Risk and return profile of options
A long option has risk limited to the premium paid and unlimited profit potential; a short option has unlimited downside risk and profit limited to the premium received.
The five pricing factors
Spot price, strike price, volatility, time to expiration and interest rates. Volatility and time raise both call and put premiums; a higher spot helps calls and hurts puts; a higher strike does the reverse; and higher interest rates raise calls and lower puts.
Theta
The change in option price for a one-day decrease in time to expiration — the measure of time decay. It is usually negative for a long option, whether call or put.
Time decay
The steady fall in the time value portion of a premium as expiry approaches, which is why options are called wasting assets — and why option sellers are said to be at a fundamental advantage.
Time value
The difference between the premium and the intrinsic value. An unexpired option always has some time value, and ATM and OTM options consist of nothing else.
Vega
The change in option premium for a given change, typically one per cent, in the underlying volatility. It is positive for a long call and a long put alike.

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Original explanatory writing based on the official NISM workbook for Series V-D, which is published and copyrighted by NISM. Check figures against the current edition at nism.ac.in.

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