Combine delta, gamma, theta and vega when evaluating an options position before and after an earnings announcement.
Before the release
Near-term IV often rises, lifting premiums through vega. Delta and gamma describe directional and curvature exposure, while theta reflects the high cost of carrying event premium.
The overnight gap
A large move can create substantial delta and gamma P&L before a hedge is possible. The opening option price also reflects the new volatility level and liquidity, so Greek estimates from the previous close are only a starting point.
After the event
IV commonly falls as uncertainty resolves. Long-vega positions may suffer a crush; short-vega positions may benefit but can lose more from a gap. Model price and IV changes together before entry.
A practical example
A long call correctly predicts an earnings rally, but the stock moves less than options had priced and IV collapses. Delta helps, while vega and theta can leave the trade unprofitable.
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
Which Greek matters most at earnings?
Delta, gamma and vega can all be material because price and IV may change abruptly.
Does IV always crush?
It commonly falls after uncertainty resolves, but the size is not guaranteed.
Can spreads reduce vega?
Yes, though they add caps, multiple legs and other risks.
Continue the All Greeks in Action cluster
Explore related guides: How to Measure Portfolio Option Greeks · Option Greeks Explained: Delta, Gamma, Theta, Vega and Rho · Option Greeks for Credit Spreads. For a structured sequence, use the free Level 8 – All Greeks in Action 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.