Vehicle registration plates of Argentina

Argentine license plates (in Spanish, chapas patentes or simply patentes) are used to uniquely identify motor vehicles on the roads of Argentina. The current system employs three letters followed by three digits, issued consecutively, but the license plate system underwent significant changes before the use of this format.

The history of license plates in Argentina can be broken down in two major phases, the decentralized phase (until 1972) and the centralized one (since 1972). During the decentralized phase, license plates were assigned by each municipality or by the provinces, while during the second phase, the national state took charge of standardizing and centralizing the design and style.

The first formal license plates were assigned in the 1900s, although few records exist of those. The period between 1916 and 1972 was the most prolific in designs. Since each district was allowed to issue its own license plates, it is possible to find a small piece of history of each one just by looking at their past plates.

In 1972 the national government standardized the plates, the format being one letter and six digits, with embossed characters painted white against a black background. The letter identified the issuing province (or city, in the case of Buenos Aires), with the numbers issued consecutively in each jurisdiction. The letter usually was the first letter of the province's name, but for multiple provinces beginning with the same letters, some provinces were issued other letters (such as X for Córdoba, P for Formosa, A for Salta, Q for Neuquen and N for Misiones); this standard is still used in the ISO 3166-2:AR geocode.

The only two districts to ever surpass one million plates, thus generating a conflict in formatting, were the province of Buenos Aires and the capital, the city of Buenos Aires. The issue was resolved by halving the height of the letter and adding another number below it.

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