SELECT LOGINPROPERTY('sa', 'DaysUntilExpiration')
Note: If you get a null while executing the query, then either the login is not a valid login or your Operating System does not support password policies. You should run this query on a SQL Server box installed on Windows Server 2003 or later.
Similarly you can get additional login information using the following query:
SELECT name,
create_date,
modify_date,
LOGINPROPERTY(name, 'DaysUntilExpiration') DaysUntilExpiration,
LOGINPROPERTY(name, 'PasswordLastSetTime') PasswordLastSetTime,
LOGINPROPERTY(name, 'IsExpired') IsExpired,
LOGINPROPERTY(name, 'IsMustChange') IsMustChange
From sys.sql_logins ;
Read more: SQL Server Curry