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Key Takeaways
- A cash-secured put collects premium and reserves the full strike-price obligation rather than relying on borrowed buying power.
- Assignment buys 100 shares per contract at the strike, with an effective cost equal to strike minus premium received.
- Maximum profit is the premium, while maximum loss is substantial if the stock falls toward zero.
- The strategy fits a neutral to moderately bullish view and a genuine willingness to own the stock at the effective purchase price.
- A cash-secured put and a covered call at the same strike and expiration have closely equivalent expiration payoffs.
What is a cash-secured put?
A cash-secured put is an options strategy that sells a put and reserves the cash required to buy the shares if the put is assigned. The seller collects premium up front. If the put is assigned, the seller buys 100 shares per contract at the strike, for an effective cost equal to the strike minus the premium received.
One standard equity put represents 100 shares. Choose the strike as a stock purchase price, then compare the premium and resulting effective cost.
The cash funds the assignment obligation: the $4,700 in reserve buys the shares if the put is assigned, and the trade’s result is the short put’s payoff on top of that cash.
How to calculate cash-secured put profit, loss, and breakeven
XYZ trades at $50. A trader who wants to own 100 shares at an effective price below $47 sells one 47 put with 30 days to expiration for $1.50 per share.
- Reserved collateral: 47 strike times 100 shares = $4,700
- Premium received: $1.50 times 100 shares = $150
- Breakeven and effective cost: $47 minus $1.50 = $45.50
- Assigned at $44: pay $4,700 for shares worth $4,400, net loss $150 after premium
- Maximum loss if XYZ falls to $0: $4,550
At $47 or higher at expiration, the put has zero intrinsic value and earns its full $150 credit. At $44, the position loses $150. Assignment buys 100 shares for $4,700, with a $45.50 effective cost per share after the premium.
At $47 or higher at expiration, the put has zero intrinsic value and retains the full credit. At $46, it has $100 of intrinsic value, leaving $50 profit. At $44, it has $300 of intrinsic value, producing a $150 loss after the credit. Loss begins below the $45.50 breakeven.
Assignment purchases 100 shares at $47. The account pays $4,700; the $150 premium supplies the difference between the strike and the $45.50 effective cost. The broker's order preview shows the cash it reserves for that obligation.
Payoff at expiration
Illustrative figures from this page's example, priced by the InsiderFinance options profit calculator. Probability assumes 25% volatility, a 4% rate and 30 days to expiration.
- Max Profit
- $150.00
- Max Loss
- -$4,550.00
- Break-Even
- $45.50
Interactive payoff loads as you reach it
Load this setup on live SPY options. Move the strikes and scrub to any date.
Build This StrategyHow to choose a cash-secured put strike
Start with the company and purchase price you want to evaluate. Use price structure, put walls, and options flow to compare strike locations. Then calculate the premium, effective purchase price, and complete dollar loss for each candidate.
Compare the put with buying shares immediately. In the example, 100 shares bought at $50 cost $5,000 and participate in the stock’s full appreciation. The put collects $150 and establishes a lower effective acquisition price through assignment. These are different ways to express the same bullish stock thesis.
Compare the payoff with a covered call at the same strike and expiration, including the actual entry prices and cash committed to each position. Model the 47 put in the options profit calculator: it shows the $150 credit, the $45.50 breakeven and the loss at every price below it, so the full downside sets the position size and the exit.
Managing a cash-secured put and assignment
Before expiration, current option P&L equals the opening credit minus the closing debit. A $40 buyback realizes $110 profit from the example’s $150 credit and releases the reserved cash.
Plan the position before assignment. Standard equity puts use American-style exercise, so assignment can buy the shares at any time during the contract’s life, not only at expiration. Track the resulting stock separately after the put closes.
The wheel strategy adds covered-call sales after acquiring shares. Record the realized option results and the current share value together to evaluate the complete sequence.
Risks and limitations of cash-secured puts
- Size from the full purchase, not the premium. The downside is stock-like: the example collects $150 but loses $4,550 if the stock falls to zero.
- Buy the shares instead when you expect a strong rally. Profit is capped at the premium: a rally above $47 earns only $150, while 100 shares bought at $50 keep the full gain.
- Track implied volatility while the put is open. The short put has negative vega, so a rise in implied volatility raises the cost to buy it back even if the stock has not moved.
- Keep the cash ready from the first day. An American-style put can be assigned at any time before expiration, which buys the shares earlier than planned.
- Budget the reserved cash for the full term. The $4,700 stays committed until the put closes, expires, or is assigned, which limits other uses of that cash.
Bottom line
If the shares are assigned, the 47 put’s $1.50 premium makes the effective entry $45.50, so a cash-secured put pays you to wait for your price. Sell it only at a strike where you want to own the stock, and size it from the full purchase rather than the premium.
Clear answers
Frequently Asked Questions
Sources and Further Reading
- OIC Options Assignment
- OIC: Cash-Secured Put
- Cboe: Cash-Secured Put Writing
- Cboe: Aligning Options Strategies to Portfolio Rebalancing Rules
How entries are sourced, calculated and updated: editorial methodology.