These limits are applied to messages, senders, or recipients to combat spam and mass-mailing worms or viruses.
- The maximum number of message recipients allowed in the To:, Cc:, and Bcc: fields. = 500
- The maximum number of e-mail messages that can be sent from a single e-mail client per minute = 30
- The maximum number of recipients that can receive e-mail messages sent from a single cloud-based mailbox in a 24 hour period = 10,000
- These limits apply to both internal and external recipients.
- For distribution groups stored in the shared address book, the group is counted as one recipient. For distribution groups stored in the Contacts folder of a mailbox, the members of the group are counted individually.
For more information from Microsoft's website, click here