 In Metra's zone-based fare system, Arlington Park is in zone E. As of 2018, Arlington Park is the 15th busiest of the 236 non-downtown stations in the Metra system, with an average of 1,738 weekday boardings.The Arlington Park station was designed originally to serve just the Arlington Park Race Track, but now serves postal employees at the Processing and Distribution Center in Palatine as well as residents of southeast Palatine and west Arlington Heights, although a fence blocks most of the access to the station from the Palatine side.Despite its original purpose as a racetrack station, Arlington Park is located along the Union Pacific / Northwest Line's main line, rather than a spur or a sidetrack.