Synthetic Long
A synthetic long combines a long call and a short put to mimic owning stock. Learn how it replicates share ownership and why traders build one instead of buying shares.
A synthetic long combines a long call and a short put at the same strike to mimic owning 100 shares of stock. The two options together move almost exactly like the shares would, up and down, for little or no cash out of pocket.
It is options recreating a stock position from parts, which sounds abstract until you see the payoff line up. Let me build it.
Two Options That Act Like Stock
Owning stock means you gain when it rises and lose when it falls, dollar for dollar. A synthetic long reproduces that with two option legs at the same strike.
You buy a call, which gains when the stock rises, and you sell a put, which loses when the stock falls. Put them together and the combined position climbs when the stock climbs and drops when it drops, tracking the shares closely. The call gives you the upside, the short put gives you the downside obligation, and the pair behaves like 100 shares without your buying them.
Watch It Work
Apple is at $200. Instead of buying 100 shares for $20,000, you build a synthetic long at the $200 strike:
- Buy the $200 call for $6 a share
- Sell the $200 put for $6 a share
- Net cost: about $0, since the two premiums roughly cancel
Apple rises to $220. Your call is worth $20 a share while the put you sold expires worthless. You gained about $2,000, the same as if you had owned the shares.
Apple falls to $180. Your call expires worthless, but the put you sold is now worth $20 a share against you. You lost about $2,000, again just like owning the shares. The synthetic long tracked the stock both ways.
Why Build One
If it acts like stock, why not just buy the stock? Synthetic longs have specific uses.
Capital efficiency. You control 100 shares' worth of exposure for little or no cash up front, though you must hold margin against the short put. That frees capital compared with paying full price for the shares.
Flexibility. Traders use synthetics to adjust positions, capture pricing differences between options and stock, or build exposure where borrowing or shorting the stock is awkward. The building block also underlies the risk reversal, which is a synthetic long using out-of-the-money strikes.
The important caution is the downside. Because you sold a put, a synthetic long carries the same large downside as owning stock: if Apple falls hard, you lose just as a shareholder would, and the short put can be assigned. It is stock-like risk, not capped-option risk. Its mirror image is the synthetic short.
- A synthetic long is a long call plus a short put at the same strike.
- It mimics owning 100 shares, gaining and losing like the stock.
- It costs little up front but requires margin for the short put.
- It carries stock-like downside, not capped-option risk.
Pop Quiz
Three quick questions to see what stuck. Pick an answer and the explanation shows up right away.
What two legs make a synthetic long?
Buy a call for the upside and sell a put for the downside, and the pair mimics owning stock.
The stock falls hard. What happens to a synthetic long?
The short put means a synthetic long has full stock-like downside, not the capped loss of a plain long call.
What is one reason to build a synthetic long instead of buying shares?
You get 100 shares' worth of exposure for little cash up front, though you hold margin against the short put.
Bottom Line
A synthetic long is a stock position built from options: a long call for the upside and a short put for the downside, at the same strike. Together they track the shares closely, for little or no cash out of pocket.
Just respect what you replicated, including the risk. A synthetic long carries the same large downside as owning stock, because the short put makes you lose right along with a shareholder in a fall. It is a capital-efficient way to be long, not a way to cap your risk.
Keep going: the pieces are the long call and the short put, the bearish mirror is the synthetic short, and the out-of-the-money version is the risk reversal.