RM 10225.120 Social Security Number (SSNs) for Passport Applications
Passport applications contain a space for the applicant's SSN. Applicants question whether or not an entry is mandatory in this space.
Internal Revenue Code 26 USC 6039E requires a passport applicant to provide his or her name and SSN. The Department of State (DoS) must routinely provide this information to the IRS.
Any applicant who fails to provide the required information is subject to a $500 penalty enforced by the IRS. If SSA has not assigned an SSN to an individual, DoS permits an entry of zeros.
NOTE: Only U.S. citizens can obtain U.S. Passports.
For additional information, see the SSNAP User Guide.