Postal codes in Poland

In Poland, postal codes were introduced in 1973. They are five-digit codes of two-then-three digits, with a hyphen between them. The first digit indicates one of the 10 large postal regions the country is divided into. These areas do not follow the administrative divisions. The second and third digits specify a particular smaller region (originally the number of a regional sorting office, there was one in every county), and the last two are the number of a postal delivery branch.

Clients receiving particularly large volumes of mail may have their own unique postal codes; the same goes for PO Box lobbies of the largest post offices.

Postal codes are written in Poland before the city/town/locality name, e.g. 00-001 Warszawa.

The first digit of a Polish postal code specifies the large area (postal region) to which the address concerned belongs. The numbers run clockwise around the map of Poland, from Warsaw (0) in the central east of the country, through east, south, west and north and then back to Łódź (9), close to the geographical centre of Poland. Each region is operated by one of the Poczta Polska's regional divisions (oddział regionalny), located in the following cities:

Codes in the format N0-9NN, e.g. are reserved for bigger clients (e.g. "Telewizja Polska, 00‑999 Warszawa"), and internal postal use, (e.g. "60-900 Poznań 2" when addressing post office #2 in Poznań).

Such postal codes route the mail directly to the recipient, therefore a street address is not necessary. This is similar to the French CEDEX.

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