Cedex (France)

Postal codes were introduced in France in 1964, when La Poste introduced automated sorting. They were updated to use the current 5 digit system in 1972.

France uses five-digit numeric postal codes, the first two digits representing the département in which the city is located. The département numbers were assigned alphabetically between 1860 and 1870, but later changes (such as renaming and splitting of départements) mean that the list is no longer in strictly alphabetical order. The system also extends to French overseas departments and territories, and also includes Monaco. Note that postcodes in both départements of Corsica commence with the "20" historically assigned to Corsica before it was split into two départements, which are now numbered 2A and 2B.

The last three digits identify a more precise location, 000 being in general reserved for the préfecture. However, in Paris, Lyon and Marseille, the last two digits indicate the arrondissement. For example, 80000 corresponds to Amiens, which is the préfecture of the Somme or département 80, while 69008 corresponds to the 8th arrondissement of Lyon.

The postal code (French: code postal) consists of five digits. In metropolitan France the first two digits are the number of the département where the post office in charge of delivery to a town is located. There are some places where this is different from the department where the place is located. In the Overseas Departments and Territories, the first three digits identify the département or territory. The digits 00 are used for Military addresses. The digits 20 are used for all of Corsica; the split of the island into two départements was not followed by a change in the postal codes.

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