In exchange-based trading, the term North American session refers to the trading period defined by the securities trading hours of North American and South American exchanges. This session runs from around 2:30 PM GMT until around 9:00 AM GMT (winter) or 1:30 PM GMT until 8:00 AM GMT (summer).
The North American session is one of three sessions which make up the full stock exchange trading day: The Asian session, the European session and the North American session. The Asian session is the first to open (11:00 PM GMT until 8:00 AM GMT), followed by the European session (7:00 AM GMT until 4:00 PM GMT) and the North American session (2:30 PM GMT until 9:00 AM GMT).
The overlaps between the Asian and European sessions and between the European and North American sessions are typically among the busiest trading hours.
In forex trading, the North American session is typically referred to as the New York session due to the importance of New York exchanges in forex trading.
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