Fallout 76 has already received one huge patch during the course of the game’s BETA event. Now, in addition to installing that patch again, Bethesda has announced a second Fallout 76 day one patch; presumably addressing more issues which arose during the BETA. However, the two patches together will be larger than the base game, and bring the total file size up to almost 100 GB when it launches on the 14th of November.
The file sizes were reported by PSU via console screenshots. The actual file size of Fallout 76 without either of the patches is 45.04 GB. In fact, the game is now available to pre-load on Xbox One, and will soon be available for pre-load on other platforms too. However, what cannot currently be pre-loaded is the Fallout 76 day one patch. Combined with the 30 GB patch which launched during the BETA and which will need to installed anew in the main game, the total day one patch is around 54.64 GB. Together with the base game, that makes Fallout 76 close to a massive 99.68 GB. (The exact size is likely to differ slightly on different platforms.)