Cancel any premium Yahoo! services you are subscribed to by logging into Yahoo! Billing. If you delete your Yahoo! account, but you fail to cancel these services, you will still be billed for them.
Save any emails, Flickr photos, addresses, Geocities Web pages, or other information you need that is contained within Yahoo!'s sites. Once you delete your Yahoo! account you cannot reactivate it.
Visit the Yahoo! Account Deletion page. Sign in, or verify your password.
Read the information on the Yahoo! Account Deletion page. It explains everything you are deleting.
Confirm your password at the bottom of the page.
Enter the captcha code.
Click the button that says "Terminate My Account." Your account will be deactivated from the data**** and you will no longer be able to access it. It will take about 90 days for your information to be deleted from Yahoo!'s servers.