Outlook Client Size Guidelines

Mail Message

The Mail message size limit is 150MB. The message size includes recipients, body of the message, headers, and attachment size.

Mail Rule

The Mail Rules size limit is 64KB. The limit size can be increased to 256KB for a mailbox if needed. Unfortunately, we do not have a set number of rules that can be made, but the more complex a rule, the more space it takes up.

Junk Mail Rule

The Junk Mail block/allow sender list size limit is 512KB.  This limit cannot be increased. However, you can save space by blocking/allowing entire domains instead of individual email addresses. For example, if badguys@badguys.com is the email address that you desire to block, you can block badguys.com. However, you do not want to do this for popular domains such as gmail.com, msstate.edu, msn.com etc. because you will cease to get email from anyone at these domains.

When you ‘Junk’ an email the default setting is to add the specific email address. Instead, you might want to block the entire domain when possible.


Article ID: 1471
Wed 10/24/18 11:13 AM
Thu 5/16/19 1:41 PM