If $2500 or more child support is owed, the person who owes child support is "ineligible" for a passport. See Child Support Payments and Getting a U.S. Passport issued by the US Department of State.

Passport Denial Program was created by the Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) of 1996 that is operated under the auspices of the Federal Tax Refund Offset Program. Under the Passport Denial Program, obligors with child support arrearages of at least $5000 that are submitted to the to the Federal Office of Child Support Enforcement (OCSE) for Tax Refund Offset are forwarded to the U.S. Department of State, which "flags" the obligor's name and refuses to issue a passport in the event they apply for one.

After the obligor makes arrangements to satisfy the arrears, States can decertify them with OCSE, which then requests that the State Department remove them from the program. This program is automatic, meaning that any obligor that is eligible will be submitted to the State Department unless the State submitting the case for Tax Offset specifically excludes them from the Passport Denial Program.

So the next step to obtain a passport is to request that the Office of the Attorney General exclude the obligor from the Passport Denial Program.

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