Also known as: Short Put · Naked Put (without the cash set aside) · CSP
Bullish — collect premium. Max loss = strike − credit if assigned.
Shape illustration on a normalized underlying — open the Lab below to price it on a real option chain.
You collect a premium for the obligation to buy 100 shares at the strike if assigned, holding enough cash to cover the purchase. Either the put expires worthless and you keep the premium, or you buy a stock you wanted anyway — at a discount to where it traded when you sold the put.
The classic income strategy on quality names you would be happy to own. Works best when implied volatility is rich (you are paid more for the same obligation) and on stocks with real fundamentals underneath.
The stock can fall far below the strike — you still buy at the strike. Maximum loss is the strike times 100 minus the premium (if the stock went to zero). "Cash-secured" caps the leverage, not the downside of ownership.
Similar: Near-identical payoff curves — both collect premium and profit in flat-to-up markets (put-call parity makes them synthetic twins).
Different: CSP holds cash and gets assigned INTO the stock; covered call already owns the shares and gets called AWAY.
Similar: Both profit when the stock stays up.
Different: Adding the long lower put turns it into a Bull Put Spread with a hard floor — far less capital, capped worst case.
New to options? Start with the free curriculum — or see which strategy fits your outlook.
Educational content — not investment advice. Options involve substantial risk and are not suitable for every investor. All trading on Opus Options Trading is simulated.