SA

SA is an abbreviation. It can stand for different things.

 Countries and territories 
It can refer to Schengen Area
It is the official two letter shorthand for Saudi Arabia.
It is the official state abbreviation for South Australia.
It is used to mean Saline County, Kansas
It is sometimes used to refer to South Africa. The official two letter shorthand for that country is ZA.
It is used to informally refer to South America.

 Cities 
It is used to mean San Antonio, Texas
It is used to mean San Andreas, California
It is used to mean St. Albans, Hertfordshire

 Organizations 

It is used to mean the Sturmabteilung, during its existence from 1919 to 1945.
It can refer to S.A. (corporation). This is a special type of company.