Does sending an email to multiple recipients multiply the attachments to exceed max size limit?

Question

When sending an email to multiple recipients are the email text and attachment size multiplied by the total number of recipients?

Exchange email sending outside my organisation.

For example, if I send an email ("Dear all, please see attachments") to 5 people and I attach 10MB worth of attachments.

Does the mailbox use 50MB worth of space or 10MB of space with the record that 10MB was sent multiple times?

Answer 1

In your sent items, it will be one message with a 10MB attachment.

In each of the recipients' inboxes, it will be one message with a 10MB attachment.

As it travels through your Exchange organization, it will be one message with a 10MB attachment, until it is bifurcated.

Bifurcation will occur if the message needs to take different paths to reach different recipients. So if all five recipients are in the same external organization, your server and their server should transmit one message with a 10MB attachment between them.