This article is from the Mongolia FAQ, by Oliver Corff with numerous contributions by others.
Available area codes are:
Ulaanbaatar 01
Darxan 037
Dornod, Qoïbalsan 061
Arxangaï 073
Bayan-Ölgiï 071
Bayanxongor 069
Bulgan 067
Gow'-Altaï 065
Gow'-Sümber 075
Darxan-Uul 037
Dornogow' 063
Dundgow' 059
Zawxan 057
Orxon 035
Öwörxangaï 055
Ömnögow' 053
Süxbaatar 051
Sälängä 049
Töw 047
Uws 045
Xowd 043
Xöwsgöl 041
Xäntiï 039
Baganuur Düüräg 031
Nalaïx Düüräg 033
At present the telephone system in Ulaanbaatar is under reconstruction
which implies that certain numbers are changed. Ulaanbaatar used to
have 5-digit telephone numbers until 1992. Those numbers which then
began with a 2 are usually converted by placing a 3 in front of the
leading digit. Other numbers were changed later. Some numbers still
retain the 5-digit order.
 
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