Yes, TDS Email accounts have sending limits, which vary depending on method you use to access your TDS Email. If you use TDS.net (Web mail), you are limited to sending 100 messages per hour; SMTP is limited to sending 500 messages per hour. The maximum number of messages that can be sent per day from any TDS Email account is 5,000.
IP-based rate limit is 20 messages every 5 minutes. Users attempting to connect to TDS Email servers from outside the TDS network can only send 50 messages per hour.