In principle, the restrictions applicable to the monitoring of internet use also apply to the monitoring of employee emails. There are, however, specific rules due to the nature of email. For instance, a review of email traffic will include the email header and will therefore not be anonymous; emails are more likely to contain private information relating to employees; and employees can only exercise limited control on the emails they receive.

Because it is difficult to monitor emails anonymously, a sporadic monitoring of email use, limited to the header information, is permitted. The monitoring must be done in accordance with a monitoring policy and an acceptable use policy must be issued to govern the use of email and, in particular, to prohibit certain uses of email. Employees also must be informed in writing in advance of any email monitoring and of the fact that the monitoring allows identification of both the employee and the sender or recipients of the emails.

Notwithstanding the right to monitor the email header information, the employer may not access the content of an employee's private emails. Distinguishing between a private and business email is not always easy without examining an email's content. If there is doubt about the private or business nature of an email, the employee must be consulted and if the employee states that the email is private, it may not be accessed without the employee's consent.