What is Jesus's Mother Mary's Last name?

Answer 1

Greetings,
Mary lived in a time when there was no last names for the common people. Someone was known as son or daughter of the Male parent. Or known by where they were from.
Also, Mary's name was a title of position in the Nazarene community of which she lived. Her mother did not call her Mary as a child. Her original given name is lost to history.

Answer 2

We'll have to ask her when we see her in Heaven.
I Cr 13;8a
11-30-6