http://support.chess.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=61&nav=0,2
USER name

Don't forget to ask about your reafer points.
Um... refer, that is, as in referral/referred (click here).
To be safe, maybe you its best you don't mention "reafers" at all, bro.
Hi all,
wondering if there is a way to change a user name? I invited a friend who typo-ed then registered before proof reading.
Is it for all eternity or can something be done?