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Put option

The right to sell at the strike price. It gains value as the underlying falls, which makes it the standard way to buy insurance on a position.

Updated 2026-09-05

A put gives you the right to sell the underlying at the strike price until expiry. It gains value as the price falls, which makes it the standard instrument for insuring a position you want to keep.

The insurance framing is the useful one. Buying a put below your entry price caps your loss for a known cost, exactly like an excess on a policy, and like a policy it expires and has to be renewed. Doing it continuously is expensive, which is precisely why the seller is willing to write it.

Selling a put obliges you to buy the shares if assigned. Done deliberately with the cash set aside, that is a cash-secured put and it is a reasonable way to enter a position you wanted anyway.

See also

  • Call optionThe right to buy at the strike price. It gains value as the underlying rises, and it expires worthless if the underlying never gets there.
  • Strike priceThe price at which an option can be exercised. Its distance from the current price determines almost everything about how the option behaves.
  • Cash-secured putSelling a put with the cash set aside to buy the shares if assigned. You are paid to agree to buy at a price you were happy with anyway.

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Educational content, not investment advice. Angie explains how a valuation is built so you can judge it yourself. What you do with that is your call.

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