Humanities › History & Culture Social Security Number Allocations by Location Where Was the Social Security Number Issued? Share Flipboard Email Print Blend Images - Hill Street Studios/Brand X Pictures/Getty Images History & Culture Genealogy Vital Records Around the World Basics Surnames Genealogy Fun American History African American History African History Ancient History and Culture Asian History European History Inventions Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Kimberly Powell Genealogy Expert Certificate in Genealogical Research, Boston University B.A., Carnegie Mellon University Kimberly Powell is a professional genealogist and the author of The Everything Guide to Online Genealogy. She teaches at the Genealogical Institute of Pittsburgh and the Salt Lake Institute of Genealogy. our editorial process Kimberly Powell Updated March 17, 2017 The first three digits of a person's Social Security number numbers can often help you to determine where your ancestor may have possibly been living when his/her SSN was issued (see exceptions below). These numbers can also be helpful in determining which listings in the SSDI may belong to your ancestor. The first three digits of a person's Social Security number were, prior to 1973, determined by the state where the person applied fo their social security card. Since that time, the first three digits have been assigned based on the ZIP Code of the mailing address on the Social Security number application. The chart below shows the first 3 digits of the social security numbers assigned throughout the United States and its possessions. SOCIAL SECURITY NUMBER STATE CODES * The same number, when shown with more than one area, means that certain numbers have been transferred from one State to another, or that an area has been divided for use among certain geographic locations. Learn more about the other numbers in the Social Security Numbering Scheme.