Employment of U.S. Citizens
When a job is open to “all U.S. citizens”, it means anyone with U.S. citizenship, or who is a national (a resident of American Samoa and Swain Island), may apply. You can verify your citizenship with the Self-Check through E-Verify (uscis.gov), if available in your state of residence.
An agency may hire a qualified U.S. citizen into the competitive service, excepted service, or Senior Executive service, if it is permitted to do so by the annual appropriations act and the immigration law and the agency's specific laws and internal policies.