Analyzing September Trading Trends in Cboe Global Markets: Assessing Short-Term Sentiment and Q4 Volatility Positioning

Cboe Global Markets' September 2025 trading data reveals a surge in activity across asset classes, reflecting heightened investor engagement and evolving risk perceptions. According to a Cboe press release, the average daily trading volume (ADV) for U.S. options hit a record 20.5 million contracts in September, a 46% year-over-year increase. The release said this outperformance was driven by robust demand for index options, including the S&P 500 (SPX) and Mini-SPX (XSP), which set quarterly and monthly volume records. Meanwhile, the release also noted that global equities trading saw U.S. on-exchange matched shares rise 38% to 1.7 billion, with Canadian, European, and Australian markets posting double-digit gains.

The volatility landscape, however, tells a more nuanced story. The Cboe Volatility Index (VIX), a key barometer of market anxiety, closed at 16.36 in September, aligning with a VIX price forecast. Analysts note that the VIX remains within a moderate volatility corridor, with support at 15.25 and resistance at 17.68, per that forecast. While the index has not broken out of this range, its positioning suggests investors are bracing for potential macroeconomic shocks, such as shifts in manufacturing PMI data or central bank policy moves, as noted in a Monexa analysis.

A critical development in September was the deployment of Cboe Hanweck's European volatility analytics across Options Technology's infrastructure, as reported in a Business Wire release. The deployment provides real-time data on implied volatility, option Greeks, and theoretical pricing, enhancing European market participants' ability to manage risk and refine trading strategies, according to the release. This integration underscores Cboe's broader push to democratize volatility analytics, a trend that could amplify liquidity and transparency in global options markets, according to CBOE open interest trends.

Short-term sentiment is further illuminated by open interest trends. Total open interest in Cboe products rose 0.3% to 26,719 contracts in September, with the 12-Sep-25 expiration adding 32 contracts, according to MarketChameleon data. Notably, put open interest outpaced calls, with the put/call ratio climbing to 0.6-a 3.3% increase over five days. This skew suggests investors are increasingly hedging against downside risks, a pattern consistent with cautious positioning ahead of Q4.

For Q4 volatility positioning, preliminary revenue per contract (RPC) guidance offers insight. Cboe projects RPC for multi-listed options at $0.054 and index options at $0.926, reflecting stable pricing dynamics, per the Cboe press release. These figures imply steady demand for volatility products, particularly as investors navigate potential earnings seasonality, geopolitical tensions, and the Federal Reserve's policy trajectory.

In conclusion, September's data points to a market balancing optimism and caution. While trading volumes and European volatility analytics signal structural strength, the VIX's range-bound behavior and rising put open interest highlight lingering uncertainties. Investors entering Q4 should monitor macroeconomic catalysts and Cboe's evolving product suite, which is poised to shape volatility strategies in an increasingly interconnected global market.