Verified answer

Go here:

http://help.yahoo.com/l/us/yahoo/edit/changing_use...

Read all the information, and then click on the "Account Deletion" link.

Or you can just go straight to the Account Deletion page:

https://edit.yahoo.com/config/delete_user

It is fairly difficult to cancel your yahoo acount. I would log into yahoo mail and click on the 'help' button in the right hand corner. Type 'deleting my acount' into the search box. Follow the directions carefully and you should be good to go.

Click the link below for all the info on deleting your yahoo account

https://edit.yahoo.com/config/delete_user