France introduced postal codes in 1964 with the advent of automated sorting by La Poste, later updating to the current five-digit system in 1972. The first two digits of each postal code indicate the département where the city is located. Originally assigned alphabetically between 1860 and 1870, the numbering system has since been altered due to renaming and administrative changes.

This system extends beyond mainland France to its overseas departments and territories, as well as Monaco. Corsica’s postal codes still start with “20”, a legacy of when it was a single département, despite now being divided into 2A and 2B.

The last three digits refine location identification:

  • 000 is generally reserved for the préfecture of a département.
  • In Paris, Lyon, and Marseille, the last two digits indicate the arrondissement.
  • For example, 80000 corresponds to Amiens, the préfecture of Somme (département 80).
  • 69008 refers to the 8th arrondissement of Lyon.

French postal codes consist of five digits and are structured based on départements. In metropolitan France, the first two digits represent the département where the responsible post office is located—though some exceptions exist where the post office differs from the actual département.

For Overseas Departments and Territories, the first three digits indicate the département or territory. Special codes include:

  • 00 for military addresses.
  • 20 for Corsica, which retained its original numbering despite its split into 2A and 2B.

The final three digits further specify the local postal office:

  • Most regular postal codes end in 0, except for Paris, Lyon, and Marseille, as well as Overseas Territories.
  • Non-zero endings may indicate CEDEX codes (for businesses and institutions) or newer postcodes.

Paris, Lyon & Marseille

In these cities, the last two digits correspond to municipal arrondissements:

  • Before 1972, addresses would note the arrondissement separately.
  • Example:
  • 8 rue Chambiges, Paris 8e → Became 75008 Paris.
  • The 16th arrondissement has two postcodes: 75016 (south) and 75116 (north).

Préfectures & Sous-Préfectures

Each département’s préfecture (main city) has a postal code ending in 000 (e.g., 18000 Bourges). Sous-préfectures often use a XXX00 postcode, but populous cities may have additional subdivisions.

Village & Cross-Département Codes

Many adjacent villages share a single postal code linked to a larger post office (e.g., 64150 covers multiple towns). Occasionally, villages are served by post offices outside their département, resulting in codes that begin with another département’s digits (e.g., 49123 Le Fresne-sur-Loire instead of 44, since it is linked to Ingrandes in Maine-et-Loire).

Overseas Territories Postal Codes

Each overseas territory has a distinct three-digit prefix:

  • 971 – Guadeloupe
  • 972 – Martinique
  • 973 – French Guiana
  • 974 – Réunion
  • 975 – Saint-Pierre and Miquelon
  • 976 – Mayotte
  • 984 – French Southern Territories
  • 986 – Wallis and Futuna
  • 987 – French Polynesia
  • 988 – New Caledonia

In 2008, La Poste proposed adding 977 (Saint Barthélemy) and 978 (Saint Martin) due to their new status as overseas collectivities. Here, the trailing zero is omitted to maintain the five-digit format.

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