Stands for the New York Mercantile ExchangeÂ’s ACCESS trading, which is an internationally accessible after-hours trading system. ACCESS stands for American Computerized Commodity Exchange System and Services. The system is accessible over the Internet and is available after regular trading hours have ended for the day. NYMEX ACCESS trading opens at 3:15 p.m. Eastern time, Monday through Thursday, and runs as late as 9 a.m. the next morning, depending on the specific contract. Sunday evening sessions open at 7 p.m. Trades are executed on the basis of price and time submitted, with the first order at the best price taking priority in execution. The system provides anonymity.