Selling a put option means you agree to buy a stock at a specific price (the strike price) before a set expiration date, and in exchange, you collect an upfront payment called a premium. If the stock stays above that strike price, you keep the premium as profit and never have to buy anything. If the stock falls below the strike price, the buyer of the put can force you to purchase the shares at the agreed-upon price, even though they’re now worth less on the open market.
How the Trade Works
Every options contract involves two sides. When you sell (or “write”) a put, you’re taking the opposite side of someone who bought that put as a form of insurance. The buyer paid you a premium for the right to sell their shares to you at the strike price. You collected that premium immediately, but you now carry an obligation: if the buyer exercises the contract, you must purchase 100 shares per contract at the strike price, regardless of where the stock is trading at that moment.
Say a stock is trading at $50 and you sell a put with a $45 strike price for a $2 premium. You immediately collect $200 (since each contract covers 100 shares). If the stock stays above $45 through expiration, the put expires worthless and you walk away with that $200. If the stock drops to $38, the put buyer can exercise the contract, and you’re required to buy 100 shares at $45 each, paying $4,500 for stock currently worth $3,800.
Your Breakeven Point
The breakeven price for a put seller is the strike price minus the premium you collected. In the example above, your breakeven is $43 ($45 strike minus the $2 premium). If the stock is at exactly $43 when you’re assigned, you’ve paid $45 per share but effectively only $43 after accounting for the premium you pocketed. No gain, no loss.
Your maximum profit is capped at the premium you received. No matter how high the stock climbs, $200 is the most you’ll make on this trade. Your maximum loss, on the other hand, is substantial. Theoretically, the stock could drop to zero, meaning you’d be forced to buy shares at $45 that are worthless. Your loss in that worst case would be the strike price minus the premium, multiplied by 100 shares: ($45 – $2) × 100 = $4,300.
When Assignment Happens
Assignment is the moment when the put buyer exercises their right and you’re required to follow through on your obligation to buy the shares. According to FINRA, as long as your short options position remains open, you can be assigned on any day equity markets are open. Most U.S.-listed stock options are American-style, meaning the holder can exercise at any time before expiration, not just on the expiration date itself.
In practice, early assignment is uncommon unless the stock has fallen well below the strike price or the expiration date is very close. But it can happen, and you need to be prepared for it. If you’re assigned, your brokerage will automatically deduct the cash from your account and deposit 100 shares per contract at the strike price. This happens regardless of whether you wanted to own the stock at that moment.
Cash-Secured Puts vs. Naked Puts
There are two ways to sell a put, and the difference comes down to whether you’ve set aside the money to back up your obligation.
A cash-secured put means you keep enough cash in your account to buy the shares if assigned. If you sell a $45 put, you set aside $4,500. This approach limits your practical risk because you’ve already committed the capital. Many brokerages require this for standard options accounts, and it’s the version most individual investors use.
A naked put means you sell the put without reserving the cash to cover assignment. Your broker requires you to post margin instead, which is typically a fraction of the full purchase price. This frees up capital for other trades, but it introduces a serious danger: if the stock drops sharply, your broker may demand additional margin on very short notice. If you can’t meet that margin call, your position gets liquidated at a loss. The Options Industry Council rates naked puts as one of the riskiest strategies available, second only to naked calls, because assignment would force you to scramble for cash to settle the purchase by the settlement date.
Why Investors Sell Puts
The two main reasons are income generation and buying stock at a discount.
Income-focused investors sell puts on stocks they consider stable, collecting premiums repeatedly over time. If the stock never dips below the strike price, they simply keep the premium and move on to the next trade. This can produce steady returns in flat or rising markets, though a sudden downturn can wipe out months of accumulated premiums in a single assignment.
Value investors use put selling as a stock acquisition strategy. If you like a $50 stock but think it’s a bit overpriced, you could sell a put at $45, effectively saying “I’d be happy to buy at $45.” If the stock drops and you’re assigned, you’ve purchased shares at a price you were already comfortable with, and the premium you collected lowers your effective cost basis even further. Some investors layer multiple strike prices, selling puts at $45, $40, and $35 on the same stock. If the stock keeps falling, they accumulate shares at progressively lower prices while collecting larger premiums at each level (premiums tend to increase as strike prices move closer to the current stock price during a decline).
What You Need to Get Started
Selling puts requires an options-approved brokerage account. Most brokers have tiered approval levels, and selling cash-secured puts generally falls into a lower tier that’s accessible to moderately experienced investors. Naked put selling requires a higher approval level and a margin account, and brokers typically want to see significant trading experience and account balances before granting access.
You’ll also need enough buying power to cover the potential assignment. For cash-secured puts, that means having the full strike price times 100 shares in cash or cash equivalents. For margin accounts, the requirement varies by broker but typically involves an initial margin deposit plus the ability to meet ongoing maintenance requirements if the position moves against you.
One practical detail worth knowing: each standard equity options contract covers 100 shares. So when you see a premium quoted at $2, the actual cash you collect is $200. And if you’re assigned on a $45 strike, you’re buying $4,500 worth of stock, not $45 worth. Sizing your positions relative to your total account value matters, because a single assignment on an outsized position can tie up most of your capital in one stock.