The name users of Wikimedia projects choose for themselves is not set in stone. Any bureaucrat on local wiki can change your username if you have fewer than 50,000 edits. You can only be renamed to an account that does not exist (Using mw:Extension:Renameuser). Contact any local bureaucrat and ask for instructions. For the English Wikipedia, see en:Wikipedia:Changing username.
If your wiki has no active bureaucrats, leave a request at Requests for username changes.
Note that this only changes the username on one specific wiki. See also Steward requests/SUL requests.
How to change names 
- Please do not request name changes on this page.
- Do not create the new account you want to change names to.
- On each wiki where you want your username changed, please ask a bureaucrat (type special:listusers/bureaucrat) to carry out the change. Sometimes Project:RENAME redirects to the local request page.
- If you have an unusual request – for a name change across many different wikis, for a change on small wikis that do not have a bureaucrat, or if you have already created the account you wish to change to, add a request to Requests for username changes.
How it works 
On request, bureaucrats can change user account settings and article histories such that all previous edits of a given user are attributed to the new name. This has been done several times in the past, either voluntarily, or forced due to our policy on offensive usernames. Account deletion is not carried out on Wikimedia projects, so if you wish to become anonymous after making edits with your account, the way to achieve this is to change username.
When a name is changed, the previous account ceases to exist, and the user may immediately log in with the same password under the new name. The user may wish to re-create the old account to prevent impersonation. In the case of forced name changes, the old account will be recreated and then blocked. Signatures in talk pages can be changed manually if desired. The deletion log and the upload log are not altered.