Short Put / Cash-Secured Put
A short put, sometimes called a naked put, is a bullish to neutral options strategy created by selling a put and collecting premium up front. It does not have unlimited risk; the downside is large but capped if the underlying falls to zero, and the cash-secured version is commonly used as a disciplined way to potentially buy stock at an effective price below the strike while getting paid to wait.
A short put consists of selling a put option and taking in premium up front. In exchange, the seller accepts the obligation to buy the underlying at the strike price if assigned.
The strategy is often called a naked put when the position is not fully backed by cash. When the seller sets aside enough capital to buy the shares if assigned, it becomes a cash-secured put.
Because the seller gets paid first, the short put profits if the option expires worthless or can be bought back for less than the original credit.
A short put does not have unlimited risk. The worst-case outcome is that the stock falls to zero, in which case the loss is the strike price minus the premium received.
That means the risk is economically similar to buying the stock at an effective cost basis of strike minus premium. It is still substantial risk, but it is bounded.
Maximum profit is limited to the premium collected and occurs if the underlying finishes at or above the strike price at expiration. In that outcome, the put expires worthless and the seller keeps the full credit.
The breakeven at expiration is the strike price minus the premium received. Below that level, losses begin, and the worst-case outcome occurs only if the stock falls all the way to zero.
Example: Stock at 50
Suppose you sell the 45 put for 2.00. Your total credit is 2.00, or $200 per contract before fees.
Maximum profit: 2.00, or $200 per 1-lot before fees.
Breakeven: 45.00 – 2.00 = 43.00
Maximum loss: 43.00, or $4,300 per 1-lot before fees, if the stock falls to 0.
If the stock stays above 45, the put expires worthless and the full credit is retained. If the stock drops below 45, the seller may be assigned and effectively buys shares at a cost basis of 43 after accounting for the premium collected.
The short put is fundamentally a willingness-to-buy-stock trade. You are being paid today for agreeing to buy shares later at the strike price if the market falls far enough.
A cash-secured put is simply a short put where you keep enough cash available to buy the shares if assignment happens. Many investors use this version because it makes the obligation explicit and keeps the position sized like a potential stock purchase.
In practice, this can be a disciplined way to try to acquire stock at a target level. If you are assigned, you buy the shares. If you are not assigned, you keep the premium.
Limit Buy Order vs. Cash-Secured Put
Limit order at 45: You only buy if the stock trades down to your target, but if it never reaches that price, you earn nothing while you wait.
Cash-secured 45 put sold for 2: If the stock stays above 45, you keep the premium. If it falls below 45 and you are assigned, your effective share cost basis is 43.
This is why a cash-secured put is sometimes a great alternative to a limit order: you are still expressing a willingness to buy at a chosen level, but you get paid for making that commitment.
The strategy is only appropriate if you truly want to own the stock and are comfortable with stock-like downside risk after assignment. If the stock gaps sharply lower, you may still end up buying it above the new market price.
Delta: The short put generally benefits if the stock rises or stays above the strike.
Theta: Time decay usually helps because the seller benefits as option value erodes over time.
Vega: Rising implied volatility usually hurts, while falling volatility tends to help.
Gamma: The position is short gamma, so downside moves can make the trade deteriorate more quickly as the stock falls.
Before expiration, a short put’s mark-to-market value depends on price, time remaining, and implied volatility. Many traders choose to close early and retain part of the credit rather than holding all the way into expiration and assignment risk.
In practice, the trade tends to perform best when price stays above the strike or rises, while implied volatility remains stable or falls after entry.
When it fits
- You are neutral to bullish on the stock.
- You would genuinely be willing to own the shares at the strike.
- You want to collect premium while waiting for a better entry.
How the trade wins
- The stock stays above the strike.
- Time passes and extrinsic value decays.
- Implied volatility falls or remains contained after entry.
How the trade loses
- The stock drops through the strike and keeps falling.
- Implied volatility expands.
- You sell more puts than you are prepared to secure with cash or own as stock.