Welcome to Fallout Answers. Type your question below so others may answer it. Remember to read the policies and guidelines before asking.

Vault 101 and Vault 112. All the others were social experiments.

Erm, you might wanna take out Vault 112. If you think about it, it was a "toychest" Vault, designed to be the plaything for Dr. Braun. While this wasn't intended by Vault-Tec, it still counts as a "social experiment" Vault. So only Vault 101 is "non-hostile", and that can change depending on player actions.

Vault 21.

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.