The german phone code 0331 represents Potsdam in Brandenburg.
Potsdam
Different spellings of the Phone Code 0331
0331
(0331)
0331-
0331/
+49331
+49 (331)
+49-331
+49 (0) 331
0049331
0049 (0) 331
Calling from abroad to Potsdam
Note for calls from abroad: In addition to the German country code (+49 or 0049) you can omit the foregoing zero of the dialling code for Potsdam. So you can dial +49331... and add the number of the phone line you want to reach.
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