If you want to delete your account on a single site, the Help Center explains how.
On your user page, under "Edit Profile & Settings" (1) a "Delete Profile" link (2) will appear:
Note: If you are suspended, visiting the Edit Profile page will give you an error page because you cannot edit your profile while suspended. You can still access the Delete Profile page though by accessing the link directly, either through the help center article or by selecting the "I need to delete my profile" option on the contact page.
Carefully read the next page. If you're sure you still want to delete, mark the checkbox (3) and click the Delete Profile button (4):
After doing this, one of two things will happen:
- If you have never posted or voted more than once on your profile, your account will be immediately deleted.
- Otherwise, the account will be scheduled for deletion. During that time, you can cancel the deletion request by visiting your profile and clicking the cancel link in the banner at the top. Otherwise, it will be deleted after (approximately - see below) 24 hours.
What happens to my content? Can I request it be deleted as well?
Content you've posted on the site is owned by you, but licensed to Stack Exchange, and you therefore cannot request that it be deleted with your account.
However, certain posts you've made that have a score of -1 or lower will be deleted with your account: this includes answers, closed questions, and open questions with no positively-scored answers. (This does not apply on meta sites.)
What if I'm suspended, rate-limited, or banned from posting questions or answers?
Unfortunately, deleting your account while you are suspended by a moderator or rate-limited or banned by the automated quality filter will not remove any restrictions placed on your account. They will simply be re-applied to any new accounts you create.
What will happen to my votes? Will other users be impacted?
Unless you had a very high reputation score, your votes will be invalidated and other users will have their reputation recalculated as if your votes were never cast. Additionally, other users will lose reputation from approved suggested edits where you were the final approver. (Bounties you awarded will be kept.)
If you did have a high reputation score, your votes may be kept (or more accurately, moved to the Community user) to prevent high-impact, widespread changes to other users' reputation. See the next section for more info.
Why wasn't my account deleted immediately after the timer expiring?
Accounts are not deleted immediately after the timer expires, but by a scheduled task that runs once an hour. Thus, you may see a notice that says "this account is scheduled for deletion [x] minutes ago", e.g. "5 minutes ago". This is intentional and by design; your account will be deleted within an hour of the timer expiring.
If your account has a very high reputation score, it will not be deleted approximately after the 24-hour timer expires, as above. Deletion will be held up while a developer checks your account for evidence of voting fraud (to see if you qualify for preserving votes, per the last section). During this hold-up, you may not see a deletion notice on your profile; please do not request deletion again, as this will prolong the process.
What will happen to my pending bounties and close, reopen, delete, or undelete votes?
If you had any pending bounties or votes while your account is deleted, those will be moved to (owned by) the Community user. In the case of bounties, you can no longer manually award them and they will be awarded automatically at the end as they normally would.
I want my account deleted on all Stack Exchange sites. How do I do this?
You will have to request deletion of your account on every single site on which you have a profile individually. As a matter of policy, the SE team does not process deletion requests manually anymore (except for Area 51 profiles, which cannot be deleted by the user, and deletion requests from high-rep users which are automatically fielded to developers to potentially preserve votes, which requires no separate intervention from the user).
Your network profile on stackexchange.com will be automatically deleted within 24 hours (whenever it attempts to sync again) unless you have ever manually logged in directly on stackexchange.com - in that case, you have a physical profile there and it will need to be deleted by staff.
Any questions you've asked that have a score of 1 and otherwise meet the automatic deletion criteria for
RemoveAbandonedQuestions (1 year old, no answers, low views, etc.) will be subject to automatic deletion by the Community user. (This doesn't apply to meta sites, as this specific deletion routine doesn't run on meta sites.)
Unless your votes were preserved, users will lose the +2 rep awarded to them if you were the final user to approve one of their suggested edits. This is an anti-abuse feature.
We used to automatically cull old, inactive accounts after 6 months as documented on the blog (When is an Account Abandoned?). However, we briefly stopped culling inactive users on May 3, 2017. Note that as of May 2018, there was an announcement that inactive accounts would once again be culled, this time after two years; this will be rolled out in June 2018.