"Optonline webmail" or "Optimum Online Email" is a web-based email client providing email addresses to users. Messages are stored on the Optimum Online web server, indefinitely for Optimum Online standard users and indefinitely (within storage limits) for Optimum Online Ultra 50 and Optimum Online Ultra 101 users.
Users can access email using Optimum Online Email or Classic Mail, as well as using a mobile device or a email program or POP client. When using a POP client, user's emails are stored on the computer's hard drive instead of on the Optimum Online servers. Optimum Voice customers can also access their voicemail messages directly by email.