West Ham will play FSV Mainz 05 in the pre-season Betway Cup clash this summer.
The Hammers and Mainz will meet on Tuesday 31st July at Kufstein Arnea in Tyrol in Austria.
The 2018 Betway Cup match will kick off at 18:30 CEST (17:30 BST).
The 2018 Betway Cup will be the fourth time the Hammers have played the pre-season competition, facing Werder Bremen at the Boleyn Ground in the inaugural fixture in 2015. The Hammers then played against Italian giants Juventus in a thrilling first match at London Stadium at the start of the 2016/17 season. A two-legged tie with Werder Bremen in Germany followed last summer, with a goal from Marko Arnautovic on his full debut the highlight of the second contest.
West Ham and Mainz last met in a pre-season fixture in the summer of 2013, a game in which the Irons scored through Academy graduate Joe Cole.
