Nonimmigrant Visa Applicants who reside in Belgium: Follow the instructions to apply for a visa and select an available appointment: https://ais.usvisa-info.com/en-be/niv/information/faqs#need_earlier_appt. If you have imminent travel, request an expedited visa appointment and be specific about your purpose of travel in the expedite request: https://ais.usvisa-info.com/en-be/niv/information/faqs#need_earlier_appt. If you are requesting an expedited appointment and you are not a Belgian citizen, you must describe how you are a resident of Belgium in your expedite request.
Nonimmigrant Visa Applicants who do not reside in Belgium: There is no restriction on individuals not residing in Belgium to make an appointment in Brussels. However, the wait time for an appointment is much longer for non-residents of Belgium. U.S. Embassy Brussels does not have the capacity to approve expedited visa requests from individuals not residing in Belgium for any reason, no matter how urgent. If you do not live in Belgium and you have an urgent need for a visa appointment, you must request an expedited appointment with a U.S. embassy or consulate in the country in which you reside.