I would like to pull SID for all users in our AD.
I am able to other columns from property such as givenname, Samaccountname, email, etc, but when I pull sid, it returns null.
How can I pull sid for all users in our domain using powershell?
Thanks
Anne,
welcome to the forum. 
When you carefully (re-)read the documentation for the cmdlet Get-ADUser you will read that it retrieves a default set of user object properties.
To retrieve additional properties use the Properties parameter. For more information about how to determine the properties for user objects, see the Properties parameter description.
The examples 3 and 4 show this as well.