Telephone numbers in East Germany


Upon the division of Germany after World War II into West Germany and East Germany, telephone numbers in East Germany were administered independently from the telephone network in the west, despite their common telecommunication history.
East Germany was assigned telephone country code 37 by the International Telecommunication Union by bilateral agreements in ITU Notification 980 of 10 March 1966.
Telephone calls between East and West Germany required international dialling with the international call routing prefix 00 and country code for calls from West Germany to East Germany, and 06 49 from East Germany to West Germany.

Canonical numbers and local shortcuts

The East German telephone network did not only consist of a strictly hierarchic star topology, but had additional links connecting areas directly. Thus, each area had one "canonical" prefix involving the central offices and a number of shortcut prefixes 02... through 05... bypassing those and reducing toll charges. For example, Zwickau had the canonical prefix 0074, but had different "shortcut" prefixes" from other areas, valid only in those - e.g. 036 from East Berlin. These "shortcuts" were not ported to the West German numbering plan.

Berlin

Because both parts of the divided Germany did not consider any location in Berlin a part of a "foreign country", both parts of the city had special prefixes for each other: West Berliners could call East Berliners with the prefix 0372. Similarly East Berliners could call West Berliners using the prefix 8-49, as if they were calling a local number.
Dialing pattern: 2-xxx xxxx

Integration into the West German telephone network

On 15 April 1992, area codes were integrated into the West German numbering plan, with permissive dialing in effect for the old codes including the old country code until 1 June 1992. East Berlin had already been reassigned with 030 area code. All area codes had the second digit into the "canonical" code replaced by 3. In places, the code was changed entirely.

Retirement of country code 37

After the reunification of West and East Germany, country code 37 was retired. This permitted the ITU to open a new numbering block, 37x, for country codes. Following the dissolution of the Soviet Union, some countries that previously used the code 7 adopted a prefix from the new block, e.g., Lithuania adopted the code 370. This included some European microstates that had previously used a network of a surrounding country. For example, Monaco adopted 377, replacing 33.