Synthetic Put
Short stock + long call = same risk profile as owning a put option.
What is a Synthetic Put?
A synthetic put replicates the payoff of a long put option by combining a short stock position with a long call at the same strike price. If the stock falls, the short stock position profits in the same way a long put would. If the stock rises, the long call's gains offset the losses on the short stock position — capping the maximum loss at approximately the premium paid for the call. By put-call parity, this combination is theoretically equivalent to owning a put with the same strike and expiration. Synthetic puts are used when actual put options are not available on a particular security (for example, on an ETF or security where puts are illiquid or unavailable), or when the synthetic construction produces a cheaper effective premium than the listed put. Market makers regularly use synthetic positions for arbitrage and hedging.
When to use it
Use a synthetic put when you want bearish exposure through a put-like payoff but cannot obtain a real put option at an acceptable price or liquidity. This can occur when the underlying has listed puts with very wide bid-ask spreads, or when a specific expiration or strike is unavailable. The synthetic put is also used when you already hold a short stock position and want to add a defined-risk cap on losses — buying a call against an existing short converts it into a synthetic put with bounded upside loss. In most retail trading contexts, a real put option is simpler and more cost-effective — understand the mechanics of the synthetic before assuming it is cheaper, as borrowing costs on the short stock can significantly erode the edge.
Structure
Key Metrics
Tips & Best Practices
- 1Always compare the effective cost of the synthetic put (call premium + borrow costs) against the price of an equivalent listed put — the real put is often simpler and cheaper.
- 2Watch borrow costs on the short stock — high borrow rates (common on "hard to borrow" stocks) can make the synthetic significantly more expensive than a real put.
- 3The call must be purchased simultaneously with the short stock to ensure the position is immediately hedged — executing legs separately creates unhedged risk windows.
- 4Margin requirements for short stock are typically higher than for buying a put — factor this into your capital allocation when comparing the two approaches.
- 5If a real put becomes available at a reasonable price after you have established the synthetic, consider converting by covering the short stock and selling the call, then buying the real put.
- 6Market makers use synthetics extensively for inventory management and arbitrage, not as speculative tools — retail traders should generally prefer real options for simplicity.
- 7Understand that put-call parity is theoretical — in practice, dividends, early exercise risk, and borrow costs create pricing differences between real and synthetic positions.
- 8A synthetic put on a dividend-paying stock requires careful attention to ex-dividend dates: the short stock position owes the dividend payment, which reduces the effective profit.
See it in action
Model a Synthetic Put with a real ticker. See the P&L chart, heatmap, and exact breakevens.
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