Topicbox has a strict anti-spam policy, and may not be used for the purpose of sending commercial or marketing mail in any quantity.
Topicbox also has rate throttling, which will go into effect if the system detects what it believes to be a mail loop, DDOS, or other mail volume situation that would negatively effect performance either of Topicbox or a receiver's email system.
Within those restrictions, Topicbox is designed to handle all of an organization's email. If these limits are not sufficient to your organization's needs, please talk to us.
Basic: 1000 messages + 100/user daily
Plus: 2000 messages + 200/user daily