What is considered a minor for passport purposes?

For U.S. passport purposes, a minor is defined as anyone under the age of 16. Children under 16 must apply in person with both parents or legal guardians present, and additional documentation and consent requirements apply.

However, applicants who are 16 or 17 years old are not considered minors in the same way, but there are still some special requirements. At least one parent must be present during the application process.