What Is a Put Option?
A put option is a right, not an obligation, to sell an asset at a fixed price before a set date. It behaves like insurance on a holding, with the premium as the cost and the strike minus that premium as the breakeven.
How it works
A put gives you the right to sell at a fixed price before a set date. If selling at that price is not useful, you do nothing and the contract expires.
The payoff is the mirror of a call. Rising to the left as price falls, flat and negative to the right. The flat part is the premium; the rising part is the protection.
The three numbers
Strike 100, premium 4, and a date.
| Maximum loss | 4 — the premium |
| Breakeven at expiry | 96 — strike minus premium |
| Below 96 | profit rises as the share falls |
| At or above 100 | the option expires worthless |
The maximum gain is large but not unlimited, because a share can only fall to zero. That is the one asymmetry separating a put from a call in the other direction.
Held alongside shares, it is insurance. The share falls, the put rises, and the combination has a floor. Everything about how insurance is priced applies directly.
Below the strike is not yet profitable. At 98 the put is worth 2 against 4 paid. The line crosses zero at 96.
In practice: the two ways it is used
As protection, it caps a holding’s downside for a period. The cost is known in advance, the floor is known in advance, and the whole arrangement expires on a date.
As a directional position, it profits from a fall without the borrow costs, recall risk and unbounded loss described on short selling. The trade is that a put has a deadline and a short position does not.
Protection is priced by demand for protection. When markets fall, expected volatility rises, and puts get more expensive at precisely the moment people want them. Buying insurance after the fire has started is a general problem, and here it has a visible price.
And it expires whether or not it was needed. Measured on the model here, half the days gone leaves 70% of the extrinsic value — so the wait costs more in its second half than its first.
Its sensitivity is not constant. Far above the strike a put barely reacts; near and below it, it moves close to one-for-one against the share. Delta is the name of that.
What a put is not
It is not free protection. Insuring a portfolio continuously costs the premium continuously, and across a long calm stretch that cost is substantial.
It is not a short position. A short has no expiry and unbounded loss; a put has a deadline and a capped one. They express a similar view with different failure modes.
It is not automatically the cheap way to be bearish. Where expected volatility is already elevated, the premium already contains the fear, and the position needs a larger move than it appears to.
And it is not a substitute for size. A position too large to hold comfortably is not fixed by buying a put; it is fixed by holding less, which costs nothing.
When it fails
A flat market expires it. Nothing bad happened, the protection was not needed, and the premium is gone — which is exactly how insurance works and still feels like a loss.
Buying after the fall is the characteristic error. The premium has already repriced, so you pay the elevated price for protection against a move that has partly happened.
Rolling protection forward repeatedly is expensive. Each roll pays a spread — wider on options than the 2% of a bar this site measures on the underlying — and a year of monthly rolls is twelve of them.
Choosing a strike too far away is the fourth failure. A cheap put with a distant strike protects against a catastrophe and not against the ordinary bad quarter that actually arrives.
And treating a profitable put as a reason to hold is the fifth. Protection that has worked is protection that has already paid; the question of whether to keep the underlying is separate.
A sixth is buying protection permanently. Insuring a holding every month of every year is a continuous drag that, across a long rising stretch, can cost more than the drawdown it was bought to avoid. Protection bought for a defined reason and a defined period is a decision; protection bought always is a fee.
The way to decide is to price the alternative. Holding less of the underlying achieves a similar reduction in exposure, costs nothing, and does not expire. A put earns its premium only where the holding genuinely cannot be reduced — a concentrated position, a tax reason, a period you want to sit through rather than sell into — and naming that reason before buying is what separates a hedge from a habit.
The original data
32 of the 24,971 videos measured for this site cover put options, at a median of 46,668 views — twice the supply of calls and a lower median, which usually indicates the topic is being answered at a more basic level than it is being asked.
The figures here are computed from the stated contract — strike 100, premium 4 — so the breakeven at 96, the −4 floor and the decay profile all follow from that specification rather than from anywhere else. Any real contract can be worked the same way before it is bought, which is the only reliable way to know what has actually been purchased.
Related
Call options are the mirror and reading both together is the fastest way to learn the shapes. Implied volatility explains the price of protection. And cash-secured puts is the other side of this contract, sold rather than bought.
Puts were the thing that finally made me understand that options are priced, not just bought. The first time I looked at protection during a genuinely frightening week, the price had already moved to reflect exactly how frightening it was.
— Michael Whitman
This page is educational, not financial advice. Test every idea on your own charts before risking money.