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Cash-secured put explained: how it works, outcome by outcome

A cash-secured put is a way to say, "I'd buy this stock at a lower price," and collect a premium while you wait. Here's how it works, and what happens if the stock keeps falling.

Beginner guide · 9-minute read · Updated 2026-10-21

The deal in one line

You sell a Put option. The buyer pays you a premium now. In return, you agree to buy 100 shares at the strike price if they choose to sell.

"Cash-secured" means you keep enough cash in your account to pay for those 100 shares. Your broker sets that cash aside until the put is gone.

If puts and strikes are new, start with options trading basics.

Why people use it

• They'd be happy to own a stock, but at a lower price than today.
• They'd rather collect a premium while waiting than place a plain limit order.
• They accept that the stock could fall far below their price.

A worked example (an illustration, not a trade idea)

A made-up stock, XYZ, trades at $50. You'd buy it at $45.

You sell one 30-day put with a $45 strike for $1.00. You collect $100 today. Your broker sets aside $4,500 ($45 × 100), the cash to buy the shares if needed.

Every outcome at expiry

The honest picture

Read that table again. The most you can make is the premium. The most you can lose is almost the whole strike price.

That's not a reason to never use it. It's the reason to only use it on a stock you'd truly want to own at that strike, sized as if you were buying the shares today.

Compared with a plain limit order

Say you'd buy XYZ at $45 either way.

That last row matters. A limit order buys the moment price touches $45. A put usually decides at expiry. Sometimes you miss the shares you wanted.

Picking the strike

A higher premium always comes with a higher chance of buying, at a price closer to today's. Our guide on how options are priced explains why.

What assignment looks like

If XYZ closes below $45 at expiry, you'll usually be assigned. The $4,500 leaves your cash, and 100 shares appear in your account. US stock options can also be assigned before expiry, though that's less common for puts well before the date.

Our options assignment guide shows each step.

What happens next: the "wheel"

Some people, once assigned, sell a covered call on the new shares. If those shares get called away, they sell another put. That loop is often called "the wheel."

It's just the two strategies taken in turn. It carries the same main risk: owning a stock that keeps falling. See the covered call guide for the second half.

How to size it

Treat a cash-secured put like buying 100 shares at the strike. Ask:

1. Would I buy 100 shares at $45 today? Is $4,500 a size that fits my account?
2. If I'm assigned and the stock keeps falling, where on the chart would I sell, and what would that loss be?
3. Does that loss fit my risk rule? See how much to risk per trade.

If the share position is too big, the put is too big. A vertical spread can cap the loss for much less cash, but it caps the premium too.

Common mistakes

• Selling puts on stocks you don't want to own. Many people only want the premium. Assignment then feels like a trap.
• Selling puts because the premium is "big." A big premium usually means high Implied volatility: the market expects a big move.
• Sizing by the premium, not the strike. The risk is the $4,500, not the $100.
• Selling puts right before earnings without checking. A gap down can blow through the strike overnight.
• Calling it income. It's a premium collected for taking on a real risk.

Try it today (no money needed)

1. Pick one stock you'd genuinely like to own. Write down a price you'd pay.
2. Open its options chain about 30 days out. Find the put at or near that strike. Note the bid.
3. Fill in the outcome table above with your numbers.
4. Check it in the options profit calculator.
5. Track it on paper to expiry. Did you get the shares? Was that what you wanted?

Questions