The Northern Ireland international will be forced to sit out Albion’s trip to face in-form Liverpool at Anfield next weekend.
Evans picked up his fifth yellow card of the season in injury time in Saturday’s 1-1 draw against Tottenham Hotspur.
He had previously been booked in the matches against Crystal Palace, Everton, Bournemouth and Sunderland.
Baggies midfielder Claudio Yacob is one of seven Premier League players currently on four yellow cards so far this season.
Spain National coach Julen Lopetegui has reassured Chelsea striker Alvaro Morata that he still has a chance to earn a call up to the 2018 World Cup squad.