A BA2 file is a compressed game data archive used by Bethesda Softworks video games, such as Fallout 4. It contains 3d models, textures, meshes, sounds, and other data referenced by each game. BA2 files replaced .BSA files.

Typically, there are two types of BA2 files you may come across: A generic BA2 file that stores any type of game data. A texture BA2 file that only stores textures. While BA2 files contain important elements seen in gameplay a typical gamer will most likely never come across the BA2 file. The files are located in the game's directory and are not meant to be altered by the user. However, they can be "modded" in order to change the gameplay such as character's appearances and the music played in the game. The Bethesda Archive Extractor program is available to unpack BA2 files.