Many people may wonder what time the stock market actually opens.

For beginners who have just started trading stocks, this opening and closing time is quite important because it affects our trading activities.
I notice that the market opening period is when stock prices are highly volatile, due to pending buy and sell orders from the previous market close, and also news in the morning that impacts the fundamentals of each stock.
If you understand this timing well, it could be a good opportunity for speculation.

Let's talk about what time the stock market opens.
The Thai stock market operates trading sessions in two parts: morning and afternoon, but each session does not open immediately.
There are several steps involved.

Starting with the pre-open period, which is from 9:30 to 9:55 a.m. for the morning session.
During this time, the system gathers buy and sell orders for processing, giving traders an approximate price beforehand.
Then comes the random open time period (9:55 to 10:00 a.m.), where the system randomly selects the actual opening time to prevent price manipulation.
Therefore, the market opening time each day is not the same; the earliest is 9:55 a.m., and the latest is 10:00 a.m.

Once the market officially opens, from 10:00 to 12:30 p.m., it is the morning trading session.
During this period, orders are matched in real-time to determine the true market price.
Afterward, there is a market break from 12:30 to 2:00 p.m.

Moving into the afternoon session, from 2:00 to 2:25 p.m., there is another pre-open period.
Followed by a random open time from 2:25 to 2:30 p.m., similar to the morning.
The afternoon trading session runs from 2:30 to 4:30 p.m.

At the end of the trading day, there is a closing process.
From 4:30 to 4:35 p.m., is the pre-close period, and from 4:35 to 4:40 p.m., is the random closing time, similar to the opening.

In summary, the question of what time the stock market opens is not fixed; it depends on the system's randomness.
The approximate times are around 9:55 to 10:00 a.m. for the morning session, and around 2:25 to 2:30 p.m. for the afternoon session.
Knowing this is quite important because we cannot trade stocks all the time—only during trading hours.
If you know the exact opening times, you won't miss the crucial moments for trading each day.