Charter's $55bn (£38bn) takeover of Time Warner Cable has been granted antitrust approval by the US justice department.
The two broadcasting companies agreed the deal last May, with Charter beating rival Comcast to make a successful bid for Time Warner.
The justice department's approval was granted with conditions aimed at protecting competition. These measures include an agreement from Charter to refrain from telling its content providers that they can't also sell shows online to platforms such as Netflix.
The US government said continued growth of OVDs (online video) "promises to deliver more competitive choices and a greater ability for consumers to customise their consumption of video content to their individual viewing preferences and budgets".
"The emergence of OVDs threatens to upend the competitive landscape," the justice department added.
The Federal Communications Commission (FCC) will also have to approve the deal, and FCC chair Tom Wheeler said any approval would also come with conditions that will "directly benefit consumers by bringing and protecting competition to the video marketplace and increasing broadband deployment".
Charter has said it is pleased with both the justice department and the FCC's decisions, and added that it is confident the newly combined business "will be a leading competitor in the broadband and video markets".