Put–Call Parity
What is put–call parity?
Answer
Put–call parity tells us the no-arbitrage relationship between European call options and European put options on the same underlying, strike and maturity (with no dividends). More specifically it states that
\[
C - P = S - K\,e^{-rT},
\]
meaning that the difference between the call and put option price is equal to being long on the stock and short on a zero-coupon bond with face value of the strike.
Put-call parity is model invariant.