Office 365 Thresholds

Quota for email per account for alumni, retirees and a few employee groups 

100 Gig

Quota for email per account for active students and some employees groups

30 days

Maximum retention period for backup of items deleted from the Deleted Items folder

25 MB

Maximum attachment size

500 recipients/email

Maximum number of people you can email at a time

10,000 recipients/day

Daily maximum number of people you can email per account

300 emails/30 minutes

Sending limit set by the University’s Spam filter for each account

Note: distribution lists started in the organization’s address book count as one recipient; those in personal contacts folders are counted individually

Those with a business need email many recipients (e.g. newsletters), should use third-party providers.