There are several methods to: The "—branch BRANCH-NAME" option can be added to the commit command when you are checking in a new modification to make it the initial check-in for a new branch. Use the following command to establish a new branch with the same starting material as an existing check-in: ancient branch BRANCH-NAME BASIS NEW The name of the new branch is specified by the BRANCH-NAME argument, and the name of the check-in from which the branch breaks off is specified by the BASIS argument. You can accomplish this using the web interface if you already have a fork in your check-in tree and wish to turn it into a branch. Find the check-in you wish to make first.