Foster was scheduled to appear at an arraignment in Tampa, Fla., on Thursday, but the hearing was canceled after the charge dismissal.
Court documents obtained by TMZ Sports from Wednesday showed the State Attorney's Office in Florida threw out the misdemeanor charge against Foster that related to an alleged incident on Nov. 24 with his ex-girlfriend, Elissa Ennis.
Sources confirmed to the NFL Network that the charges were dropped, and Foster remains on the Commissioner's Exempt List.
Foster was arrested Nov. 24 in Tampa prior to a game against the Tampa Bay Buccaneers while he played for the 49ers. He allegedly struck Ennis and knocked her phone out of her hand at the 49ers' team hotel.
Ennis was also the alleged victim of a prior domestic violence incident involving Foster, but she recanted the allegations against him. Ennis later went on to admit she lied when recanting and indicated she would cooperate with authorities after the latest incident in November.
Sources told TMZ that Ennis' actions from the previous charges might have hurt her credibility, which led to its dismissal.
The linebacker was released by the 49ers the day after the charges came to light, but was subsequently claimed off waivers by the Redskins.
The 24-year-old Foster was a first-round pick in the 2017 NFL Draft by the 49ers. He has 84 career tackles since entering the league.