The IV case number format, also known as an Immigrant Visa Case Number, is a unique identifier assigned by the National Visa Center (NVC) to each applicant seeking an immigrant visa to the United States. This identification number is primarily used to track and process the immigrant visa applications and provide updates on the progress of the case. The IV case number format consists of three letters followed by ten digits, for example, ABC2019123456. The three letters indicate the embassy or consulate where the case is being processed. These letters can vary, and the most common ones are GUN, MNL, CDJ, BNC, RUN, SYD, and FLR, among others. Different types of IV case numbers may be assigned depending on the specific immigrant visa category. Some commonly used immigrant visa categories include family-sponsored preferences (F), employment-based preferences (E), diversity visas (DV), and special immigrant visas (SIV). Each of these categories has a designated prefix within the IV case number format to distinguish them from one another. For instance, a family-sponsored preference immigrant visa case number may start with the letter "F," followed by the embassy code and the ten-digit number. Similarly, an employment-based preference immigrant visa case number may begin with the letter "E," while a diversity visa case number will have "DV" as its prefix. Special immigrant visas, such as those issued to Iraqi or Afghan nationals who have worked for the U.S. government, have their unique code as well. Understanding the IV case number format is crucial for visa applicants as it allows them to track the progress of their visa applications, schedule consular appointments, and communicate effectively with the NVC or the embassy or consulate where their cases are being processed. By ensuring the accurate mention of the IV case number in all communications, applicants can expedite the visa processing and stay informed about any updates or additional documents required to proceed further. In summary, the IV case number format is a distinctive numerical identifier assigned to individuals seeking immigrant visas. It plays a vital role in facilitating the visa application process, ensuring efficient tracking, and updating the applicants on the progress of their cases. The format includes three letters representing the embassy code followed by ten digits, with different prefixes indicating specific immigrant visa categories such as family-sponsored preferences (F), employment-based preferences (E), diversity visas (DV), and special immigrant visas (SIV).