The next Fallout 4 expansion is called Vault-Tec Workshop. It comes out late in July, but Bethesda announced in a Twitter post that they will stream the content live for the first time this Tuesday. It’ll be streamed on Bethesda’s Twitch account.
— Fallout (@Fallout) July 8, 2016
Vault-Tec Workshop costs $5 and it lets players create a “massive” vault that can be filled with a slew of new items. After this expansion, only Nuka-World remains, which developers are teasing will be substantial. That will be the last expansion.