Twitter isn’t for the faint of heart, so here’s how to delete your account
First thing to note is that there’s no way to immediately delete your profile. Instead, going through these steps deactivates your account, after which it’s queued for permanent deletion. You won’t be able to deactivate your account from the mobile app, however, meaning you’ll need to visit the actual website in order to do so. Once done, Twitter will retain your data for 30 days, thus allowing you to log in and reactivate your account should you change your mind and decide you truly can’t live without #FollowFridays.
Even though Twitter will eliminate your account, it doesn’t guarantee your tweets won’t be indexed by search engines like Google and Bing. That means your tweets could still exist somewhere – a non-issue if you posted innocuous tweets. Per Twitter policy, you will not be able to reactivate your account after 30 days. If you’ve amassed a huge following, you’ll lose them forever.
If you’re ready to pull the trigger on ending your Twitter account, check out the instructions below for details.
Step 1: Navigate to Twitter and sign into your profile as you would normally.
Step 2: Click on your Avatar icon in the upper-right corner of the screen and select Settings from the resulting drop-down menu.
Step 3: Scroll down to the bottom of the page and click Deactivate Account. This will take you to one final page, with details about how deactivation works. Click the Deactivate button once you’ve read the information.
Step 4: When prompted, enter your account password to verify that you really want to deactivate your account. After that, you’re 30 days away from being free. The deactivation should kick in after a few minutes, but some of your info may be viewable on the site for a few days afterward. Rest assured, however, that it will be wiped with time!
Source: http://www.digitaltrends.com/social-media/how-to-delete-your-twitter-account/