Market Data Differences: Global Trading Hours (GTH) and Regular Trading Hours (RTH) on Sahm
Trading index options like SPX, VIX, and XSP requires understanding two key trading periods: Global Trading Hours (GTH) and Regular Trading Hours (RTH). To make informed trading decisions, it’s crucial to know the differences between these periods and how Sahm supports each one.
What are GTH and RTH?
Time Zone | Regular Trading Hours | Global Trading Hours | Curb Session |
Eastern Time | 9:30 AM - 4:15 PM | 8:15 PM - 9:15 AM | 4:15 PM - 5:00 PM |
Arabia Standard Time | 4:30 PM - 11:15 PM | 3:15 AM - 4: 15 PM | 11:15 PM - 12: 00 AM |
Note：
- The Eastern Time shown above follows Daylight Saving Time (DST). When DST ends, clocks are set back one hour. This causes trading hours in Arabic Time to shift by one hour as the U.S. transitions between Standard Time and DST.
- For SPX, VIX, and XSP, curb sessions after Regular Trading Hours (RTH) are available for participants to adjust, unwind, or close trades.
Interpreting Option Market Data on Sahm
On Sahm, data for the highest price, lowest price, opening price, trading volume, and daily/weekly/monthly/quarterly/annual candlestick charts are based on trading activities from the entire day, including both Regular Trading Hours (RTH) and Global Trading Hours (GTH). However, other statistical data is calculated based only on Regular Trading Hours, which can result in differences in observed prices, volumes, and other metrics.
Please note that Sahm currently supports index options trading exclusively during Regular Trading Hours (RTH).
