The 24-year-old was arrested by Essex police in the early hours of Sunday morning following an incident outside a nightclub in Brentwood and faces a court appearance next month.
Tomkins, who played the full 90 minutes as West Ham lost 3-1 to Manchester United at Old Trafford on Saturday, has been a regular in Sam Allardyce's side this season, starting 12 of their 17 Premier League games.
A statement from Essex police read: "A man is due to appear in court next month (January) after he was charged with assaulting a police officer outside a nightclub in Brentwood.
"Police had been contacted by security staff from the Sugar Hut Village shortly before 12:30am on Sunday, December 22 following reports of a disturbance.
"Officers arrived and arrested James Tomkins before later charging him with one count of assaulting a police officer, one count of resisting arrest and one count of being drunk and disorderly in a public place.
"The 24-year-old footballer from Priests Lane in Brentwood is currently on police bail until his appearance at Basildon Magistrates Court on Thursday, January 9, 2014."
