Both clubs were charged following an altercation just before half-time in Everton's 2-1 victory at Goodison Park on Saturday.
The incident occured when West Ham players took exception to a strong challenge from Kevin Mirallas on midfielder Morgan Amalfitano.
James Tomkins confronted Mirallas, who pushed the defender in the chest, with the centre-back falling holding his face.
West Ham boss Sam Allardyce described Tomkins' reaction as "silly" and the FA on Friday revealed that Everton and West Ham have been fined as a result of the conduct of their players.
A statement from the governing body said: "Everton and West Ham United have each been fined £20,000 after the clubs admitted breaching FA Rules in relation to player conduct.
"Both clubs were for charged for failing to control their players in the 40th minute of their fixture on 22 November 2014.
"The clubs accepted the standard penalty for this offence."