Analyze the net delta, gamma, theta and vega of bull put and bear call spreads instead of focusing only on premium collected.
Directional exposure
A bull put spread normally has positive delta; a bear call spread normally has negative delta. The long wing defines maximum expiration loss and offsets part of the short option's Greek exposure.
The seller tradeoff
Positive theta may reward time passing and negative vega may benefit from lower IV. Negative gamma means an adverse move can accelerate losses and change delta faster than a static payoff snapshot suggests.
Near expiration
When price stays safely away from the short strike, all Greeks tend toward zero. Near the strike, gamma and assignment risk can become concentrated, making the final days operationally demanding.
A practical example
A bull put spread starts with +18 delta, positive theta and negative vega. A selloff toward the short strike raises directional exposure and can combine negative gamma with an IV expansion.
This simplified example isolates selected sensitivities so their interaction is easier to understand. Live option prices also reflect the underlying price, time decay, rates, dividends, liquidity and transaction costs. Greeks are theoretical estimates, not guarantees.
Frequently asked questions
Do all credit spreads have positive theta?
They often do at entry, but net theta can change with price and time.
Is risk always defined?
A standard vertical credit spread defines expiration risk when constructed and managed correctly.
Can falling IV guarantee profit?
No. An adverse price move can overwhelm the vega benefit.
Continue the All Greeks in Action cluster
Explore related guides: Option Greeks for Debit Spreads · Option Greeks Around Earnings · Option Greeks Explained: Delta, Gamma, Theta, Vega and Rho. For a structured sequence, use the free Level 8 – All Greeks in Action course.
Apply the concept: Continue with the Short Iron Condor guide and the free Level 11 course.
Options involve risk and are not suitable for every investor. This material is educational and is not investment, tax or legal advice. Greeks are theoretical estimates, and contract terms and broker requirements can vary.