Go to Niantic’s website, and fill out your email address, and name of your account. Select the email from the subject line as “Delete account”. Check the checkbox to delete the application. Delete the Pokémon Go app from your phone.
How do I delete my Pokemon Go email?
If you want to delete your Pokémon Go account, you need to follow the steps to do so. You must enter your email address, subject line as “Delete account”, and then provide your nickname. After you do this, you must check the four boxes.