I only just realized recently that my understanding of US stock market opening hours is still a bit mixed up, so I decided to organize what I’ve figured out over the years.

To be honest, when I first started buying US stocks, the biggest thing that bothered me was the time difference. In Taiwan, US stock market opening hours are actually at night. Under standard time, they run from 10:30 PM to 5:00 AM the next day; under daylight saving time, they shift one hour earlier to 9:30 PM to 4:00 AM. The US adjusts for daylight saving time between winter and summer every year, but we in Asia don’t, so around November and March you need to pay special attention to whether the timing has changed.

Besides the regular trading sessions, you can also play around with pre-market and after-hours trading. US pre-market is from 4:00 AM to 9:30 AM (Eastern Time). In Taiwan, that corresponds to roughly 4:30 PM to 10:30 PM during standard time. After-hours is from 4:00 PM to 8:00 PM (Eastern Time), which in Taiwan is about 4:00 AM to 8:00 AM. However, liquidity during pre-market and after-hours isn’t as good, and the bid-ask spread is usually wider.

The US stock market mainly operates through three exchanges: the New York Stock Exchange, NASDAQ, and the American Stock Exchange. Their opening hours are actually synchronized, so you don’t need to worry about the times being different. But because they operate independently, prices sometimes show small discrepancies.

The most important point is also to keep an eye on US market holidays. Important days in 2026—such as January 1 (New Year’s Day), January 19 (Martin Luther King Jr. Day), February 16 (Washington’s Birthday), April 3 (Good Friday), May 25 (Memorial Day), June 19 (Juneteenth), July 4 (Independence Day), September 7 (Labor Day), November 26 (Thanksgiving), and December 25 (Christmas)—should all be marked in advance, so you don’t end up waiting for the market to open like a beginner and finding there’s no trading. Some holidays also have early market closures, typically three hours earlier than usual, either the day before a holiday or the day after, so that’s something else to watch out for.

In the end, as long as you understand how to convert US stock market opening hours to Taiwan time and remember the changes caused by daylight saving time, you won’t end up stepping into a trap. It’s a good idea to set reminders on your phone so you don’t accidentally miss the trading window.