Protective Put: how the position works

Own the shares and buy a put against them. The put sets a floor: below its strike, further falls in the stock are matched by gains in the option. The upside stays fully intact, less the premium paid. It is portfolio insurance in the literal sense, including the part where you pay a premium and usually get nothing back.

Market view: Bullish — hedged
Opened for: Debit
Maximum profit: Unlimited. The stock's upside less the premium paid.
Maximum loss: (Cost basis − K) + premium paid. Fixed and known from the day it is placed.
Breakeven: Cost basis + premium paid.

How it is built

Hold 100 shares of the underlying
Buy 1 put at strike K as protection

All figures above are quoted per share and settle at expiry. A standard equity option covers 100 shares, so multiply by 100 for a single contract.

Before expiry: the Greeks

Net delta between 0 and 1. Long vega, which is unusual for a stock holder and valuable: implied volatility rises when markets fall, so the hedge gains value from the panic as well as from the price. Short theta — the premium bleeds every day nothing happens, which is what insurance costs.

When to use it

When you must keep a position — for tax reasons, a lock-up, or conviction — through a period you consider dangerous. Its identical twin is a long call at the same strike, and comparing the two prices here is worthwhile: parity says they should match, and any gap is a financing or borrow cost worth understanding before choosing.

What goes wrong

It is expensive to maintain. Rolling protection continuously can consume much of a portfolio's long-run return.
The floor sits at the strike, not at today's price. Everything between the current price and the strike is still your loss.
Buying protection after a fall means buying it at the highest implied volatility of the cycle, which is when it is least worth the price.

A worked example

Own 100 NVDA at a cost basis of 170, now 175. Buy the 165 put, 60 days out, for 6.80.

Premium paid: $6.80 per share — $680
Floor established: $165 per share
Maximum loss: $1,180 ((170 − 165 + 6.80) × 100), whatever happens below 165
Breakeven: $176.80 (170 + 6.80)
Profit if NVDA reaches 220: $4,320 ((220 − 170 − 6.80) × 100)

Commissions, exchange fees, financing and the bid/ask spread are excluded. On a multi-leg position the spread is usually the largest of these.

Common questions

Why not just sell the stock?

Selling realises a taxable gain, forfeits dividends and the upside, and requires deciding when to buy back. The put keeps all of that intact for a known fee. If none of those apply to you, selling is usually cheaper.

Related strategies

Educational only. This page explains how a structure behaves; it is not a recommendation to trade it. Options and futures carry substantial risk, and short and leveraged positions can lose more than the amount originally invested.