The case against him was dismissed on Thursday, September 26, due to a lack of witnesses.
A restraining order against Hickerson, keeping him away from the actress, has also been lifted.
He was arrested by police on 2 May after an argument with Panettiere at her home reportedly turned physical.
Hickerson pleaded not guilty to charges and his lawyers have always maintained the actress was to blame for the bust-up.
If convicted, he faced up to four years behind bars and Hayden's family pressed the judge overseeing the case to give him a maximum sentence.
"We are hopeful that the judge makes the right decision," a statement read. "It's an important message in terms of domestic violence for all women."
Panettiere and Hickerson were first linked in August, 2018, shortly after the actress split from her fiance, former boxing champ Wladimir Klitschko - the father of her four-year-old daughter, Kaya.