Postal codes inArgentina are calledcódigos postales. Argentina first implemented a four-digit postal code system in 1958, aiming to improve mail distribution efficiency. However, it wasn't until 1998 that the more detailed and comprehensive Código Postal Argentino (CPA) system was launched, significantly enhancing both accuracy and efficiency in mail delivery.^[1] Until 1998^[2] Argentina employed a four-digit postal code for each municipality, with the first digit representing a region in the country, except in the case of the city ofBuenos Aires (which had different postal codes starting in 1000 and with the other numbers varying according to the zone). The unique codes became the base for the newer system, officially called CPA (Código Postal Argentino, Argentine Postal Code).^[3]

The CPA is not mandatory for private use, but companies that domass mailings benefit from a discount if they use the CPA. Despite this, the CPA is still not in wide use by private persons, and even government sources and private businesses often list only the base code (the old system). In order to ease the adoption of the new postal code, the former state mail company (Correo Argentino) provides a look-up feature on its website.^[4] The CPA is intended to improve the quality and speed of mail delivery, but mail without a well-formed CPA will be delivered correctly as well.

The CPA consists of three parts:^[5]

• A single letter (ISO 3166-2:AR) that references theprovince (for example, C forCapital Federal, Q forNeuquén).
• Four digits (the old postal code or a variation of it on the last digits) showing the town or city.
• Three letters, identifying a side of thecity block where the address is located.

The first letter in the CPA, which identifies the province, has its origins in the oldArgentine license plates system, which gave each province a letter, usually its initial. Since several provinces share the same initial, a few odd assignments are found (such as X forCórdoba, A forSalta, and N forMisiones). SeeISO 3166-2:AR for a complete list.

The four digits could be grouped as the following:

• 1XXX = Buenos Aires City, Buenos Aires Province North (e.g., C1420Buenos Aires City, B1900La Plata).
• 2XXX = Santa Fe (e.g., S2000Rosario, S2300Rafaela).
• 3XXX = Santa Fe, Entre Ríos, Chaco, Corrientes, Formosa, Misiones (e.g., E3100Paraná, P3600Formosa, N3300Posadas, W3400Corrientes).
• 4XXX = Jujuy, Salta, Tucumán, Catamarca, Santiago del Estero (e.g., T4000San Miguel de Tucumán, A4400Salta, K4700San Fernando del Valle de Catamarca).
• 5XXX = Córdoba, La Rioja, San Juan, San Luis, Mendoza (e.g., X5000Córdoba, M5500Mendoza, D5700San Luis, F5300La Rioja).
• 6XXX = Buenos Aires Province West, La Pampa (e.g., B6000Junín, L6300Santa Rosa, L6700Luján).
• 7XXX = Buenos Aires Province East, Center and South (e.g., B7000Tandil, B7600Mar del Plata, B7400Olavarría).
• 8XXX = Buenos Aires Province South, Río Negro, Neuquén (e.g., B8000Bahía Blanca, R8400Bariloche, R8500Viedma, Q8300Neuquén).
• 9XXX = Chubut, Santa Cruz and Tierra del Fuego (e.g., U9000Comodoro Rivadavia, U9200Esquel, V9410Ushuaia, Z9400Río Gallegos).

A combination of three letters that identifies a side of a city block.

• Official Post Office Zip Code Finder

• Communications in Argentina
• Postal codes by country

• CS1 Spanish-language sources (es)
• Articles with short description
• Short description is different from Wikidata
• Articles containing Spanish-language text