Mass or bulk emailing using Office 365


Office 365 email has limits which can prevent use of the service for mass mailing but there are alternatives available, such as the University's mailing list system.

What are the limits?

Email sent from Office 365 is subject to the standard Office 365 Limits, including: 

The above rates are set by Office 365 and cannot be altered.

External addresses

The default maximum sending limit to external addresses is set at 100 recipients per hour. However, this can be increased if there is a valid reason for a higher rate being required. Please Contact IT if you require an increase. 

Mailing List Service for non-personalised emails

The University provides a mailing list service which can allow you to create, manage and send a standard, non-personalised email to large numbers of users. The membership of the mailing list can be updated simply by cutting and pasting lists of email addresses allowing you to send email to those recipients in a controlled and recorded way. The mailing list service has a wide variety of features which includes allowing self-subscription, allow anyone to post to the list, requiring moderation or preventing sending to the list for all but specific individuals. For more details on the mailing list service, and to obtain a downloadable application form to create a mailing list, please refer to https://lists.leeds.ac.uk 

University Mailing Lists

For more information about the mailing service, include a list of all public lists, see: https://lists.leeds.ac.uk/

A mailing list is just a list of email addresses. An email sent to the mailing list will be received by everyone on it. The University has its own mailing list system.

To apply for a new mailing list you'll need to print off and complete the link to application form for lists and send it to the User Admin team (via the IT Service Desk).

Why are sending rate limits imposed?

We experienced several instances of lots of spam being sent from single University email accounts. This usually happened after a user's account was compromised.

Spam email is often sent to many recipients at once and can cause the sending site to be blacklisted by other mailing systems. This causes all mail from the University to be rejected by those systems. By limiting email sending rates, we can prevent too much spam leaving the University and reduce the risk of email from the University being blacklisted.