The premium is the price of an option: what the buyer pays and the seller receives, quoted per unit of the underlying. A NIFTY call quoted at ₹150 costs ₹150 multiplied by the lot size. Every premium, for every call and put on any exchange, can be split into exactly two parts:
Premium = intrinsic value + time value
Understanding this split is the key to understanding why options behave the way they do: why some options move almost like the index, why others melt away even when you are right, and why sellers like quiet markets.
Intrinsic value: what it is worth right now
Intrinsic value is the amount an option would be worth if it were exercised immediately. It can never be negative.
- For a call: intrinsic value = price − strike, if the price is above the strike; otherwise zero.
- For a put: intrinsic value = strike − price, if the price is below the strike; otherwise zero.
Options with intrinsic value are called in the money. Options without it are at the money (strike at the price) or out of the money. The ITM, ATM and OTM guide explains those labels.
Time value: the price of possibility
Time value (also called extrinsic value) is the rest of the premium: what buyers pay for the chance that the option becomes more valuable before expiry.
Time value = premium − intrinsic value
A far out-of-the-money call is worth nothing if exercised today, yet it still trades at a few rupees because NIFTY could rally before expiry. Those few rupees are pure time value. As expiry approaches, there is less time for anything to happen, so time value shrinks. At expiry it is exactly zero, and every option is worth only its intrinsic value.
A worked example: splitting NIFTY premiums
NIFTY is at 25,080 with four days to the weekly expiry. Here are some illustrative premiums:
| Option | Premium | Intrinsic value | Time value | Status |
|---|---|---|---|---|
| 24,800 call | 330 | 280 | 50 | In the money |
| 25,100 call | 125 | 0 | 125 | At the money |
| 25,400 call | 30 | 0 | 30 | Out of the money |
| 25,300 put | 270 | 220 | 50 | In the money |
| 25,100 put | 140 | 20 | 120 | Just in the money |
| 24,800 put | 38 | 0 | 38 | Out of the money |
Two patterns stand out. First, time value peaks at the money: the 25,100 call and put carry about ₹120 each, while options 300 points away carry ₹30 to ₹50. Near the price, the outcome is most uncertain, and uncertainty is what time value pays for. Second, deep in-the-money options are mostly intrinsic value, so they move almost point for point with NIFTY.
Now think about the buyer of the 25,400 call at ₹30. NIFTY must rise above 25,430 by expiry just to break even. If it rises to 25,300, the trader was right on direction, yet the call expires worthless: all ₹30 of time value is gone.
Watch time value disappear: the straddle
An at-the-money straddle (the ATM call plus the ATM put) is almost pure time value, so its chart is the clearest live picture of decay. Here is today's NIFTY straddle:
On a quiet day the line slopes down as time value bleeds away minute by minute. On a busy day, when NIFTY moves sharply or fear rises, the line jumps instead. Compare it with the same chart on an expiry day, when the straddle can lose most of its value by 15:30. The straddle guide explains how traders read it.
What makes time value bigger or smaller
- Time to expiry. More time means more chance of a move, so more time value. A monthly option costs more than a weekly one at the same strike.
- Implied volatility. When traders expect bigger moves (before the Union Budget, RBI policy or company results), time value rises across the chain. After the event it often collapses; see implied volatility.
- Distance from the price. Time value is largest at the money and falls off in both directions.
- Interest rates and dividends have small effects: higher rates add slightly to call time value, and an expected dividend lowers call prices and raises put prices for that stock.
How fast time value decays
Decay is not even. With a month to go, an at-the-money option loses a little each day. In the last week the daily loss grows, and on expiry day itself the remaining time value can vanish within hours. Roughly, time value shrinks with the square root of time left: an option with one quarter of the time left keeps about half its time value, not a quarter. The rate of decay is measured by theta; the theta guide covers it in depth.
How traders use the split
- Buyers who want to pay less time value choose in-the-money options or longer expiries, accepting a higher price for less decay.
- Sellers choose options that are mostly time value (at or out of the money, close to expiry), because that is the part that decays in their favour.
- Checking value. If an option has unusually large time value compared with similar strikes, implied volatility there is high: either an event is coming or the option is expensive.
- Exit decisions. A deep in-the-money option with almost no time value left behaves like the underlying itself, so holding it adds little that a futures position would not.
A useful habit is to write down the split before every trade. Suppose you buy the 25,100 call above at ₹125 with NIFTY at 25,080. You are paying ₹125 of time value, all of which will be gone at expiry. For the trade to pay, NIFTY has to rise enough, and soon enough, to build at least ₹125 of intrinsic value: above 25,225 at expiry. If you sell the same call, you are collecting ₹125 of time value and betting it decays faster than NIFTY can create intrinsic value against you. Seen this way, every option trade is a race between movement and time.
The expected move guide uses the same idea to turn the at-the-money time value into a range the market thinks is fair for the expiry.
Common mistakes
- Calling a cheap option a bargain. A ₹5 option is cheap because it is unlikely to pay. Its ₹5 is all time value, and it will most likely reach zero.
- Expecting a premium to follow the index point for point. Only intrinsic value moves fully with the price; time value can fall at the same time.
- Holding bought options through the last days. That is when decay is fastest.
- Selling time value without respecting the tail. Collecting decay works most days, but one large move can outweigh months of it.