Since Ukraine's independence in 1991, the country has used four main systems of vehicle registration plates.
The first system was introduced in 1992 and was based on the last Soviet license plate conception, regulated by the 1977 standard, but with the addition of a new regional suffix corresponding to a Ukrainian province.
In 1993, the left-hand side of the plate was modified with the addition of the national flag over the country code "UA".
1995 saw the introduction of a completely new system consisting of five digits, with a dash between the third and fourth digit, combined with a two letter suffix. It also included a two-digit region code, situated under the National Flag on the left-hand side of the plate.
In order to enable drivers using their vehicle abroad, and in order to adhere to the Vienna Convention on Road Traffic, Ukrainian regular license plates use only those Cyrillic characters where the glyph resembles a letter from the Roman alphabet; a total of 12 characters: А, В, Е, І, К, М, Н, О, Р, С, Т, Х). Before 1995, the "Я" character was also used. For some types of black-background plates can be used completely Cyrillic characters.
Some vehicles, like trolleybuses, are not required to have license plates, because they cannot leave the network they operate on and can be identified by a number painted on the vehicle and assigned to it by the local public transport authority.