static void Main(string[] args) { // Find your Account Sid and Auth Token at twilio.com/user/account string AccountSid = "ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"; string AccountSidToClose = "ACxxxxxxxxxxxxxxxxxxx"; string AuthToken = "your_auth_token"; var twilio = new TwilioRestClient(AccountSid, AuthToken); Account account = twilio.ChangeSubAccountStatus(AccountSidToClose, Twilio.AccountStatus.Closed); }