Why IV Moves
Implied volatility is derived from option prices, which are driven by supply and demand. When more traders buy options (especially puts), prices rise and IV increases. When traders sell options or demand dries up, IV falls.
But option demand doesn't change randomly. Specific, identifiable triggers cause IV to spike. Recognizing these triggers early gives you a significant trading edge.
Trigger 1: Upcoming Earnings Announcements
The most predictable IV increase happens 1-3 weeks before earnings. Companies report quarterly, and each report creates uncertainty. Did revenue grow? Is guidance positive? Are margins expanding?
IV typically begins climbing 10-14 days before the announcement and peaks the day before. Post-earnings, IV collapses (IV crush). This pattern repeats every quarter with remarkable consistency.
How to use it: If you plan to sell premium around earnings, enter 7-10 days before the announcement when IV is still climbing.
Trigger 2: Fed Meetings and Economic Data
FOMC rate decisions, CPI releases, jobs reports, and GDP data all move IV — particularly for index options and rate-sensitive sectors like banks and real estate.
The VIX typically rises 1-2 points in the days before an FOMC meeting, especially when the market is uncertain about the outcome.
Trigger 3: Geopolitical Events
Wars, trade tensions, elections, and diplomatic crises inject uncertainty that can't be modeled. The market responds by bidding up options as hedging demand surges.
Examples: VIX spiked to 82 during March 2020 (COVID), to 37 during the 2022 Russia-Ukraine escalation, and to 65 during the April 2025 tariff shock.
Trigger 4: Market Sell-offs
Volatility and stock prices are inversely correlated. When stocks drop, IV rises. A 3% SPX decline in a single day can push VIX up 30-40%. This happens because:
The correlation isn't perfect in reverse — rallies reduce IV, but slowly. The adage is: "Markets take the stairs up and the elevator down."
Trigger 5: Sector-Specific Catalysts
FDA drug approvals (biotech), product launches (tech), oil inventory reports (energy), and regulatory decisions create IV spikes in specific sectors without moving the broader market.
Biotech stocks routinely see IV double or triple before binary FDA decisions. A stock with normal IV of 40% might trade at 120% IV the week before an approval announcement.
Trigger 6: M&A Rumors and Takeover Speculation
When acquisition rumors circulate, option activity surges. Call buying drives up call IV, and the unusual activity often appears in options flow data days before any public announcement.
Unusual options activity — a spike in call volume or IV on a stock without obvious news — is frequently an early signal of M&A activity.
Trigger 7: Index Rebalancing and Expiration Events
Quarterly options expiration (especially "triple witching") and major index rebalancing events increase hedging activity. The week before quarterly expiration often shows elevated IV as institutional positions are rolled or adjusted.
Trigger 8: Low Liquidity Periods
Holiday weeks, summer doldrums, and pre-market hours show inflated bid-ask spreads that effectively increase IV readings. This is more of a mechanical effect than a true increase in expected movement, but it affects your execution costs.
How to Monitor IV Triggers
Build a calendar of known events:
OptionsPilot helps you track upcoming catalysts alongside current IV levels, so you can see when volatility is likely to expand and plan your trades accordingly.
Key Takeaway
IV spikes are rarely random. Track the calendar, monitor unusual options activity, and watch for the eight triggers above. Knowing why IV is rising — or about to rise — determines whether you should sell into elevated premiums or buy before the expansion.