Updated email sending limits for Purdue faculty, staff and students
To enhance the university’s email security and reduce the impact of compromised accounts, Purdue University is enforcing outbound email sending limits. Student email accounts have been subject to email sending limits since March. Beginning Oct. 2, faculty, staff and student workers’ accounts will also be subject to sending limits, with higher thresholds than those applied to student accounts. (Note: Any faculty or staff accounts that have bypassed the hourly or daily limits in the past six months will automatically be excluded from this change. Purdue IT will review these accounts and follow up on situations in which a more appropriate solution is available.)
These limits apply to all Purdue campus locations: West Lafayette, Indianapolis, Purdue Fort Wayne, Purdue Northwest and Purdue Polytechnic High Schools.
Student accounts are now limited to:
- Maximum of 200 emails per hour, OR
- Maximum of 500 emails per day
Effective Oct. 2, 2026, Faculty, staff and student worker accounts will be limited to:
- Maximum of 600 emails per hour, OR
- Maximum of 1200 emails per day
Users who exceed the limits may receive a Microsoft Outlook non-delivery report (NDR) containing an error similar to: ‘550 5.1.8 Access denied, bad outbound sender’
Once blocked, the account will be unable to send email until Purdue IT is contacted, the activity is reviewed, and the restriction is removed.
For additional information including instructions for restoring the ability to send messages and alternative options for reaching large groups, please read the knowledge base article “Email Sending Limits.”
If your business or academic need cannot be met using the mass emailing options listed in the article linked above, you may request a temporary or permanent sending-limit exception by submitting the exception request form.
Last Updated: Sept. 22, 2026