Cash Secured Put Calculator

By Yojana Mandon · Updated June 2026 · 2 min read · Risk disclaimer

Selling a cash-secured put earns premium and obligates you to buy the stock at the strike if assigned — a way to get paid while waiting to buy a stock cheaper.

⧉ Embed this free calculator on your site →

Key characteristics

• Keep the premium if the stock stays above the strike at expiration.
• Effective buy price if assigned = strike − premium received.
• A staple of the "wheel" strategy alongside covered calls.
• Requires cash set aside to cover assignment.

When to use a cash-secured put

Sell a cash-secured put when you would genuinely like to own a stock at a lower price and are happy to be paid while you wait. You set aside the cash to buy 100 shares at the strike, which is what makes it "secured".

If the stock stays above the strike, the put expires worthless and you keep the premium; if it falls below, you buy the shares at the strike — at an effective price reduced by the premium you collected.

Risks and management

Your risk is essentially that of owning the stock from the strike, minus the premium. A sharp decline still leaves you buying shares that are now worth less, so only sell puts on names you want to hold.

It is the first half of the wheel strategy: get assigned, then sell covered calls. If you want to avoid assignment, you can roll the put down and out for additional credit.

On the Greeks, the Cash Secured Put is vega-negative — a fall in implied volatility (such as an earnings IV crush) works in your favour, and theta-positive, so time decay adds to the position each day it is held.

Managing the trade and common mistakes

Most experienced traders take profits early rather than holding to expiration. A common rule of thumb is to close the position when you can buy back the short put for roughly 50% of the original credit — at that point, you've captured the bulk of the theta decay while eliminating the remaining downside risk. Holding on for the last few cents of premium is rarely worth the gamma exposure that builds as expiration nears.

Rolling is the primary adjustment tool for a cash secured put that moves against you. If the underlying drops and the put moves into the money, you can roll down and out — buy back the current put and sell a new one at a lower strike in a later expiration — collecting an additional credit and buying time for the stock to recover. Only roll if you still want to own the stock at the new strike; never roll purely to avoid booking a loss.

Assignment is not a failure with this strategy — it is a defined outcome you should be prepared for from entry. If you are assigned, you own the shares at your effective cost basis (strike minus credit received). The mistake is selling puts on stocks you would not actually want to hold. Liquidity also matters: always trade puts with tight bid-ask spreads and meaningful open interest, or you will give away edge on every fill.

Calculate it live

Use the free OptionProfit Cash Secured Put calculator to load a live option chain, build the trade, and instantly see the payoff chart, breakevens, probability of profit, Greeks and a Monte Carlo simulation of outcomes.

Frequently asked questions

Educational use only. Quotes are delayed ~15 minutes and nothing here is financial advice. Options trading involves substantial risk of loss. Privacy Policy · Terms & Conditions.