Cash-secured put strategy: reserve cash before selling
A cash-secured put combines a short put with money reserved to buy the underlying shares if assigned. The premium is the most the option can earn; the stock can still fall to zero. Start with a purchase price and share quantity you can fund, then assess the premium. The Options Industry Council describes this as a stock acquisition strategy.
Cash reserve and net entry price are different numbers
Let K be strike price, p premium per share, n contracts, m shares per contract and F total trade fees. This calculator assumes physical delivery and matching premium and share multipliers. The default m is 100. Check the contract specification: a corporate action can change deliverables without changing the premium multiplier. Such adjusted contracts need a separate calculation.
- Gross assignment cash = K × n × m.
- Premium after fees = p × n × m − F.
- Net acquisition cost = (K − p) × n × m + F.
- Expiration breakeven = K − p + F ÷ (n × m).
- Expiration P/L = [p − max(K − expiration price, 0)] × n × m − F.
The reserve shown is the full exercise payment. A broker may credit the premium toward its cash requirement; confirm its rules before placing a trade. Net acquisition cost describes the economics if assigned, not the cash transferred for the shares or a tax basis calculation. If fees exceed the premium, no stock price makes the option trade profitable; there is no expiration breakeven.
A $145 put: premium received and stock loss
Assume a $150 stock, one $145 put sold for $3 per share, a 100-share multiplier, 30 days and zero fees. Reserve $14,500; collect $300; net acquisition cost is $14,200, or $142 per share. These are hypothetical inputs, not market quotes. Each row assumes the position lasts to expiry.
| Expiry stock price | Share outcome | Total P/L |
|---|---|---|
| $165 | Put expires without intrinsic value | +$300 |
| $145 | No intrinsic value; assignment uncertain at strike | +$300 |
| $142 | 100 shares worth $14,200 if assigned | $0 |
| $130 | 100 shares worth $13,000 if assigned | −$1,200 |
| $0 | Shares have no value | −$14,200 |
At $130, paying $14,500 for shares worth $13,000 produces a $1,500 share loss, partly offset by the $300 premium. Holding the assigned shares does not erase that economic loss. With $2 in fees instead, breakeven becomes $142.02, maximum option profit $298 and the $130 scenario loses $1,202.
Opportunity cost: idle cash and a rally without shares
The calculator compares the assumed alternative cash yield with the yield actually earned on reserved collateral. Opportunity cost = gross reserve × (alternative yield − collateral yield) × days ÷ 365, with yields entered as decimals. At assumed yields of 4% and 0%, $14,500 for 30 days has a $47.67 cash opportunity cost. A $300 option profit is then $252.33 ahead of the cash alternative; a $1,200 option loss is $1,247.67 behind it. Equal yields make this adjustment zero. This is simple interest, with no reinvestment or tax assumption.
There is also missed stock upside. In the example, buying 100 shares at $150 would earn $1,500 if the stock reaches $165; the put earns $300. That comparison uses $15,000 for shares versus a $14,500 put reserve, excludes dividends and interest, and does not imply the two positions have equal capital needs. Fidelity discusses both downside exposure and missed purchase opportunities.
Assignment changes the position you hold
American-style puts can be assigned before expiration. At expiry, an in-the-money put is generally exercised, but exercise instructions and after-hours movement can change the outcome. This tool calculates payoff, not assignment probability. Near the strike, verify the broker's procedures rather than treating a chart line as a settlement guarantee. Read Fidelity's exercise and assignment explanation.
A covered call starts with shares and a short call; this strategy starts with reserved cash and a short put. After put assignment you own stock, and selling a call is a new trade with new risk. Rolling also closes one obligation and opens another; a credit does not cancel a realized loss.
Model the put in TradingView Options, then check the inputs
- Select the underlying and expiration in TradingView Options. Create a strategy and add one short put using S in the options chain.
- Set the strike, quantity and opening premium. Check whether the chosen price is bid, ask, midpoint or theoretical; a midpoint is not a promised fill.
- Compare the expiration payoff with this calculator. Keep collateral and cash-yield assumptions separately because the short-put leg does not establish your broker's funding rules.
- In Pineify's AI Stocks & Options Picker, inspect the available options-chain bid, ask, expiration and IV for the same contract. Record the timestamp, multiplier, fees, assignment plan and any missing quote fields in Trading Journal notes.
TradingView documents the controls in its options strategy builder guide. Neither its scenario view nor this calculator is a historical options backtest. This page takes manual inputs and does not fetch quotes. The pre-expiry curve assumes European exercise, no dividends and constant volatility; it cannot price American early exercise or liquidity costs.
Sources checked October 18, 2026. Contract conventions: OIC options basics and OIC contract adjustments. Educational calculations only, not investment advice. Losses can be substantial.
Continue with the TradingView strategies guide to compare other structures and their assumptions.