# IV Crush: Why Options Lose Value After an Event

Understand why implied volatility often falls after earnings and other scheduled events, how Delta, Vega, and Theta combine, and why getting direction right may still lose money.

Canonical: https://wiki.fcontext.com/options/iv-crush/
Fact checked: 2026-07-22

> For educational purposes only; not investment advice.

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## Direct answer

**IV crush** is a rapid decline in implied volatility after a scheduled or anticipated event resolves uncertainty. Before earnings, a court decision, regulatory result, or macro release, options may embed a large event variance. Once the outcome and immediate price jump become observable, that single-event component leaves the remaining option horizon, so both calls and puts can lose extrinsic value. IV crush is usually normal repricing, not a data error. A directional option buyer profits only if favorable spot movement and other effects exceed the volatility, time, spread, and skew losses paid for at entry.

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## Why event volatility collapses

An option's price reflects the distribution of possible future outcomes, not just whether the stock will rise or fall. A simplified local decomposition is `ΔV ≈ Delta×ΔS + Vega×ΔIV + Theta×Δt`, with Gamma, Vanna, Volga, skew, rates, dividends, and execution omitted. Event IV is not a pure forecast of the post-event stock return; it is the volatility input consistent with option prices, supply and demand, risk premia, and discrete-event risk.

As the event passes, less uncertainty remains before expiry. Near-term options containing a large fraction of event variance can reprice most sharply. Different strikes and expiries do not crush equally: skew can rotate, the front expiry can collapse while later expiries move less, and a second unresolved event can preserve volatility.

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## Direction right, option down

Suppose a call costs `$5.20` before earnings, with Delta `0.55` and Vega `$0.08` per one implied-volatility point. After the report, the stock rises `$3` but IV falls `20` points. Assume time decay, spread, and other omitted effects total `-$0.25`:

- Direction contribution: `0.55×$3=+$1.65`.
- IV contribution: `$0.08×(-20)=-$1.60`.
- Other contribution: `-$0.25`.
- Approximate change: `+$1.65-$1.60-$0.25=-$0.20`.

The call falls from `$5.20` to about `$5.00` despite the correct direction, a `$20` loss for a `100` multiplier before fees. This is only a first-order attribution: Delta and Vega change during a jump, and actual quotes include Gamma, skew, and liquidity.

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## Event-risk checklist

- Identify every event inside the expiry and its exact announcement timing relative to the trading session.
- Compare the option market's event-implied move with your scenario distribution, not with a direction alone.
- Record IV by strike and expiry, expected move, skew, term structure, Vega scaling, and executable Bid/Ask before entry.
- Stress favorable and adverse gaps together with IV drops of several sizes; do not assume spot and IV move independently.
- Separate intrinsic from extrinsic value and calculate how much favorable movement is required to offset the premium at risk.
- Use post-event historical samples cautiously; company regime, macro conditions, and market risk premium change.
- A vertical spread may reduce net Vega and premium but also caps payoff and introduces two-leg execution; it does not eliminate IV risk.
- Long straddles and strangles need realized movement large enough to overcome event premium, decay, and spreads.
- Selling elevated IV is not automatically advantageous: gaps can exceed the implied move and short options carry nonlinear tail and assignment risk.
- Size from stressed dollar loss, not from an IV percentile or a label such as “high IV.”

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## Common misconceptions

- “IV crush means the stock's volatility becomes zero.” Implied volatility falls but remains positive and maturity-dependent.
- “Calls fall after bad news and puts after good news.” Both sides can lose extrinsic value after uncertainty resolves.
- “Correct direction guarantees a profitable long option.” Magnitude, entry premium, IV, time, and execution all matter.
- “High IV must fall after every event.” Other unresolved risks or an unexpectedly large regime shift can keep IV elevated.
- “Vega predicts the exact loss.” It is a local sensitivity and changes with spot, time, and volatility.
- “The implied move is the market's guaranteed range.” It is a price-derived estimate, not a hard boundary or probability promise.
- “Selling the crush is free edge.” Short-volatility positions exchange frequent premium for gap and tail exposure.

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## Related topics

- [Implied volatility](/options/implied-volatility/)
- [Vega](/options/vega/)
- [Theta](/options/theta/)
- [Earnings options](/options/earnings-options/)

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## Primary and academic sources

- [OCC: Characteristics and Risks of Standardized Options](https://www.theocc.com/company-information/documents-and-archives/options-disclosure-document)
- [Cboe Options Institute: Options Greeks](https://www.cboe.com/optionsinstitute/option_basics/options-greeks/)
- [Options Industry Council: Volatility](https://www.optionseducation.org/advancedconcepts/volatility)
- [Black and Scholes: The Pricing of Options and Corporate Liabilities](https://doi.org/10.1086/260062)