Ssn.txt -

XXX-XX-XXXX (with hyphens) or XXXXXXXXX (unformatted). 2. Common Formatting Methods

Originally assigned by geographical region. SSN.txt

If you are using this file for a programming or data task, you might need specific formatting logic: The SSN Numbering Scheme - Social Security History XXX-XX-XXXX (with hyphens) or XXXXXXXXX (unformatted)