Email, Exchange, What is the limit to the number of recipients per message?
What's the limit on the number of recipients per message on the Exchange server?
The maximum number of recipients allowed by the Microsoft Exchange server is 5000. However, mail clients may start to experience problems if the total number of recipients exceeds around 200. Also, Exchange should not be used for mass mailings. A department wishing to send mass emails should utilize a departmental email relay server or the Massmail service: http://illinois.edu/webservices/massmail/