Name changes are officially available on Twitch! Just log into your Twitch account, go to settings, and check if you are eligible for a name change. The name must be unclaimed and your old username is kept for 6 months after the change. Check out the Twitch blog post that outlines how to do it.
From the blog:
Starting today (right now, in fact!) you can change your username once every 60 days. Simply go to your Profile Settings and beside your username you’ll see a new option to make the change.
Once you’ve changed your name, the abandoned username will be held by Twitch for a minimum of six months. After which, we may decide to return it to the pool of available usernames for the community and new users. We will not recycle partner usernames, except in special circumstances.
We often receive requests for taken but inactive usernames. Unfortunately, at this time, we still do not accept direct requests to take a name from another account. Inactive usernames are subject to our username recycle and reuse policy. Please see this blog for more information on how that works.
Please note, during the testing period for this feature, we found that certain streamers will lose access to their streamer stats upon execution of a username change. To preserve your streamer stats, you must export them prior to changing your username. It should also be noted that the URL for your channel page will change and the old one will not redirect to your new one, so be sure to update the link wherever you are using it externally.
There is a lot to consider when changing your username, but we hope you’ll get some good use out of this tool. Now get out there and change those usernames!