The period when two major forex trading sessions are open simultaneously, resulting in higher trading volume, increased liquidity, and greater price volatility. The most significant overlap occurs between the London and New York sessions (8:00 AM to 12:00 PM EST), which typically produces the largest price movements and tightest spreads of the trading day.
Example
“The forex trader focused her scalping strategy during the London-New York session overlap from 8 AM to noon EST, when EUR/USD spreads were tightest and volatility was highest.”