The company is targeting profiles that have shown no activity in the last six months. This cleansing process will start on 11 December and will be completed over a number of months.
Twitter told The Verge that it was deleting the accounts in an attempt to present more reliable information on the platform.
"As part of our commitment to serve the public conversation, we're working to clean up inactive accounts to present more accurate, credible information people can trust across Twitter."
"Part of this effort is encouraging people to actively log-in and use Twitter when they register an account, as stated in our inactive accounts policy," Twitter said.
The company said it will notify users who have not signed onto the platform in recent months that their account may be in danger of being deleted.
It should be noted that tweeting is not a requirement for keeping an account in an active state, only logging in.
Freeing up usernames
The decision will lead to the removal of the accounts of deceased persons and the deletion of their entire tweet history.
Twitter said it was considering a way to memorialise these accounts.
The process will also gradually free up usernames assigned to inactive accounts.
It is unlikely that bots and secondary accounts will be affected as long as they remain active.
