Postal codes were introduced in France in 1972, when La Poste introduced automated sorting.
Format
The postal code (in French, code postal) consists of five digits, the first two digits being the number of the département in metropolitan France where the post office in charge of delivery to a town is located. The system is also used outside Europe, in the Overseas Departments and Territories, but it is the first two digits that identify the département or territory. The digits 00 are used for Military addresses. The digits 20 are use for Corsica, in which the département numbers are 2A and 2B.
The next three numbers identify the local postal office in charge of mail delivery. A regular postcode always ends with a 0, with the notable exception of Paris, Lyon and Marseille - see below - and the Overseas Départements and Territories. Postcodes not ending with a 0 may indicate a special code, known as CEDEX (see below), or newest postcodes.
In Paris, the last two digits of the postal code indicate the arrondissement. Prior to 1972, an address in the eighth arrondissement in Paris, would be written as:
8 rue Chambiges Paris 8e
This number was incorporated into the postal code as:
8 rue Chambiges 75008 Paris
An exception to this rule is the XVIe arrondissement, which has two postal codes, 75016 (south) and 75116 (north).
Outside of Paris, the cities of Lyon and Marseille are also divided into arrondissements, which are part of the postal code:
11 rue Duhamel 69002 Lyon
2 avenue du Maréchal Foch 13004 Marseille
In each département, the préfecture (main city) has a postal code ending with 000, for example Bourges in Cher:
15 avenue du Général Leclerc 18000 Bourges
The more important the city, the simpler the postal code. The sous-préfectures are generally recognized by using a XXX00 postcode. Here is for example the postal code of a small village, Lépaud in Creuse:
16 grande rue 23170 Lépaud
And the postal code of Mortagne-au-Perche, sous-préfecture of the Département de l'Orne:
4 rue des Quinze Fusillés 61400 Mortagne-au-Perche
It is not rare that many adjacent villages share the same postal code, which is primarily associated with a bigger post office, e.G 64150 can correspond to Abidos, Bésingrand, Lagor, Lahourcade, Mourenx, Noguère, Os Marsillon, Pardies, Sauvelade and Vielleségure.
Overseas Départements and Territories use 2-digit codes starting with : 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 this case, the last zero is dropped so as to keep the 5-digit format. This is why the regular postcodes for these don't end with 0 except for the préfecture or sous-préfecture, for example :
Maison du Port 97100 Basse-Terre
4 boulevard du Général de Gaulle 97320 Saint-Laurent du Maroni
193 RN2 97439 Sainte-Rose
CEDEX
There is also a system known as CEDEX, Courrier d'Entreprise à Distribution EXceptionnelle, designed for recipients of large volumes of mail. A postal code is allocated to each large organisation or to post office box holders, ending in three unique digits, for example:
2 place Jussieu 75251 Paris Cedex 05
The '05' is for the Ve arrondissement. Ordinary deliveries would be addressed to:
2 place Jussieu 75005 Paris
It is also acceptable to include a boîte postale (post office box) number as well as the street address in CEDEX addresses.
Monaco
The French postal code system is also used in Monaco, where the postal code is prefixed with 'MC', not with 'F' for France:
12 avenue de la Costa MC-98000 Monaco MONACO
23 Avenue Prince Héréditaire Albert MC-98025 Monaco Cedex MONACO