National Visa Center (NVC) - General information ... NVC processes all approved immigrant visa petitions after they are received from the U.S. Citizenship and Immigration Service (USCIS) and retains them until the cases are ready for adjudication by a consular officer abroad. Petitions may remain at NVC for several weeks or for many years depending on the visa category and country of birth of the visa applicant. When an applicant's case is about to become current (a visa number is likely to be available within the year) the petition is forwarded to the appropriate U.S. embassy or consulate overseas. If an applicant is adjusting status in the U.S. the case will be forwarded to the appropriate USCIS office upon request by that office.