Update 5 January 2013: Now,Facebook don't allow to change your Facebook page name.However,If your page have fewer than 200 likes you can change it easily just by going to Edit Page>Update Info But you can't change the page name with 200 or more likes.
Although,If you accidentally selected a wrong or misspelled username for your Facebook page .You can change it by going to Edit Page>Update Info>Change Username>Check for your new user name availability and hit save! But note that you can change it only for once.
How To Change Your Facebook Page Name Officially?
1. At current time,you can only change your Facebook page name Not its Vanity URL/Username.The form looks like below.
2. If you select My business name has changed then you have to submit your new business name as well as its address.For ex.Any Bill.
3. If you select My Page name is misspelled,your request will be completed by them as soon as possible.So,better to select “My Page name is misspelled” in the last option saying “Why do you want to change you page name” to change your Facebook page name without any risk.
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