# Terraform Versions

You can customize which version of Terraform Atlantis defaults to by setting the --default-tf-version flag (ex. --default-tf-version=v0.12.0).

If you wish to use a different version than the default for a specific repo or project, you need to create an atlantis.yaml file and set the terraform_version key:

version: 3
projects:
- dir: .
  terraform_version: v0.10.5

See atlantis.yaml Use Cases for more details.