There are indeed three market sessions, 1. TO: Tokyo is open, this is from when the market opens at around 5am/6am to 2PM. This session is usually a passive market 2. LO:London is open from 2pm to 7pm here is an active market 3.UO: US Open, 7 to 11pm the market is active here too, so be smart to choose a pair for us to trade in sessions the.