When sending an email with classified information attached, what should the email be marked as?

When sending an email with classified information attached, marking the email as a letter of transmittal is appropriate because this designation serves as a formal communication that indicates the contents are intentional and specific. A letter of transmittal is utilized to convey or transmit information, particularly when it involves sensitive or classified materials. This classification alerts the recipient to the nature of the contents being transmitted and underscores the importance of handling the information securely.

In contrast, designating the email as a personal message or a draft only does not appropriately reflect the seriousness or security requirements associated with classified information, as these terms imply a lack of formal handling or urgency. Similarly, labeling it as a confidential inquiry would not be accurate because that suggests a question or request for information rather than a formal transmission of classified content. Use of the letter of transmittal ensures that the recipient understands the responsibility that comes with accessing the attached classified information.