What does attn stand for mail

A common abbreviation!

"ATTN" is an abbreviation for "Attention". It's often used in formal and informal writing, including emails, letters, and packages, to draw attention to a specific person, department, or topic.

For example, you might see "ATTN: John Smith" at the top of an email or package to indicate that it's intended for John Smith's attention.

In the context of mail, "ATTN" is often used to ensure that the mail is delivered to the correct person or department.