The National Visa Center is a branch of the U.S. Department of State The NVC is located in Portsmouth, NH and is responsible for processing all immigrant visa petitions after they are approved by the USCIS. Typically, the NVC gathers additional information and helps further prepare the petition for ultimate processing at the U.S. Embassy or Consular office abroad. The NVC retains all approved petitions until they are ready for adjudication abroad.