Vehicle registration plates of Bulgaria compatible with both the Cyrillic and Latin alphabets came into force: Vehicle registration plates of Bulgaria Standard Bulgarian vehicle registration plates display black glyphs (alphanumeric characters) on a white background, together with – on the left-hand side of the plate – a blue vertical "EU strip" showing the flag of Europe (or, for older-registered cars, the flag of Bulgaria) and, below it, the country code for Bulgaria: BG. The characters displayed in the main field of the plate are: The format is thus XX NNNN YY, where XX (or X) is the province code, NNNN is the serial number, and
International vehicle registration code registration plate. When the distinguishing sign is incorporated in the registration plate, it must also appear on the front registration plate of the vehicle. The requirement to display a separate distinguishing sign is not necessary within the European Economic Area, for vehicles with license plates in the common EU format which satisfy the requirements of the Vienna Convention, and so are also valid in non-EU countries signatory to the convention. Separate signs are also not needed for Canada, Mexico and the United States, where the province, state or district of registration is usually embossed or surface-printed on the vehicle registration