What Cash-Secured Puts Are and How They Work

The basic mechanics

A cash-secured put means you sell a put option on a stock and set aside enough cash to buy 100 shares at the strike price if assigned. The buyer of the put pays you a premium upfront. In exchange, you agree to buy the stock at the strike price if it falls below that level before expiration.

The "cash-secured" part means you have the full purchase amount reserved. You are not using margin or leverage. The worst-case outcome is that you buy a stock you wanted to own anyway, at a price you chose in advance, minus the premium you collected.

Why sell puts instead of just buying the stock

If you want to own a stock at $140 and it currently trades at $150, you have two choices. You can place a limit order at $140 and wait. Or you can sell a $140 put, collect premium immediately, and get the same entry price if the stock drops.

The advantage of the put: you get paid to wait. If the stock never drops to $140, the option expires worthless and you keep the premium. You did not get the stock, but you earned income on the cash that was sitting idle.

The disadvantage: if the stock drops well below $140, you are obligated to buy at the strike. The premium offsets part of the loss, but you are exposed to the full downside below your effective cost basis (strike minus premium).

Choosing a strike and expiration

Strike selection is about identifying a price at which you would genuinely want to own the stock. This is not hypothetical. If you would not be comfortable holding 100 shares at the strike price, do not sell the put.

Most cash-secured put sellers target strikes 5% to 15% below the current stock price. This provides a margin of safety while still collecting meaningful premium.

Expiration choice follows the same time-decay logic as covered calls. The 30-to-45-day window captures accelerating theta decay. Shorter expirations offer faster turnover but less total premium per trade. Longer expirations collect more premium but tie up capital for longer.

What happens at assignment

If the stock is below your strike at expiration, you will be assigned: your broker buys 100 shares at the strike price using your reserved cash. Your cost basis is the strike price minus the premium you collected.

At this point, many traders transition to selling covered calls against the shares they now own. This creates the "wheel" strategy: sell puts to enter, sell calls to generate ongoing income, and repeat. Each leg collects premium and lowers the effective cost basis over time.

Risk management

The maximum loss on a cash-secured put is the strike price minus the premium, multiplied by 100 shares. In theory, the stock could go to zero. In practice, this means you should only sell puts on companies you have researched and are willing to own through a drawdown.

Position sizing matters. Tying up $14,000 in cash to secure a single put on a $140 stock is a significant allocation. Diversifying across multiple positions and keeping individual position sizes reasonable prevents any single assignment from distorting the portfolio.