Except for a brief period during Prohibition era, ATF and its predecessor bureaus functioned within the U.S. Department of the Treasury for more than 200 years. In January of 2003, ATF’s functions and responsibilities were transferred to the Department of Justice.

The Homeland Security Act split the missions and functions of ATF into two agencies: The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) transferred to the U.S. Department of Justice, and the Alcohol and Tobacco Tax and Trade Bureau (TTB) remained with the U.S. Department of the Treasury.