Managing your account
Closing your account
If you wish to close your account, you can do so at any time on the Delete Account page. This will delete your default tumblelog along with your overall Tumblr account.
If you have created or joined an additional tumblelog beyond your default tumblelog, you can leave the additional tumblelog at any time. Just click the Members link on the Dashboard page for the additional tumblelog and then click the "Leave this group" button.
If you are the only user on an additional tumblelog, it will be deleted when you leave it. Otherwise, the additional tumblelog will continue on with its remaining members. Leaving an additional tumblelog will not delete your default tumblelog or your overall Tumblr account.