Berlin is subdivided into 12 boroughs (Bezirke in German), which are administrative units with political rights comparable to incorporated communities in the rest of Germany (although they are not separate legal entities from the city).

Effective January 1, 2001, the Berlin borough reform reduced the number of Berlin's boroughs from 23 to 12 in order to cut down administration costs. This was achieved by combining several of the old boroughs.

In detail, the old and the new boroughs relate as follows:

  New borough name Old borough names Area in km² Population
I Mitte Mitte, Tiergarten, Wedding 39.74 320,700
II Friedrichshain-Kreuzberg Friedrichshain, Kreuzberg 20.16 255,200
III Pankow Prenzlauer Berg, Weißensee, Pankow 103.07 347,100
IV Charlottenburg-Wilmersdorf Charlottenburg, Wilmersdorf 64.72 315,200
V Spandau Spandau (unchanged) 91.91 226,100
VI Steglitz-Zehlendorf Steglitz, Zehlendorf 102.50 288,300
VII Tempelhof-Schöneberg Tempelhof, Schöneberg 53.09 336,000
VIII Neukölln Neukölln (unchanged) 44.93 307,400
IX Treptow-Köpenick Treptow, Köpenick 168.43 233,700
X Marzahn-Hellersdorf Marzahn, Hellersdorf 61.74 254,000
XI Lichtenberg Lichtenberg, Hohenschönhausen 52.29 260,200
XII Reinickendorf Reinickendorf (unchanged) 89.45 245,900

(all data as of 2003)