Ukraine (similarly to most of ex-Soviet Union countries) employs a four-level (local, zone, country, international) open dialing plan. Nearly in every house or an apartment in Kyiv you'll find the local phone. If you are renting a flat, usually the landlord will cut the 0 number off, which means you wouldn't be able to call long distance but you could call all Kyiv (land) numbers and mostly all CDMA numbers for free. Note, that you will not be able to call mobile or cell phones as well, because they start from 0.
JSC Ukrtelecom (Ukrainian: Укртелеком) is Ukraine's monopolist government-owned telephone company, also active on other telecommunications markets like Internet service providing. It is the largest telecom communication carrier of fixed telephony in Ukraine, which operates more than 10 million of telephone lines, and the leader among Internet providers in Ukraine. The Company covers about 71% of the local telephony market and 83% of long-distance and international telephony market. The Company incorporates 32 branches, one of which is Utel. Now Ukrtelecom is a co-owner of 14 international submarine transmission systems, such as ITUR and BSFOCS, and a member of TEL and TAE projects. (read more Ukrtelecom Official web)
Ukraine Country Code: +380
International Call Prefix: 00
National Kyiv (Kiev) Code: 44 XXX XX XX
International Kyiv Code: +380 44 XXX XX XX
Mobile Call Prefix:
*internationally or mobile to mobile: +380 (operator code, for ex. Kyivstar 67) XXX XX XX
*in-country or mobile to mobile: 0 ~ operator code, for ex. Kyivstar 67 XXX XX XX
For all non-local and mobile numbers, the required trunk prefix is '0' followed by an auxiliary dial tone after it. Then with the following "0" for international calls. Mainly for historical reasons, zone codes are very often named with a leading "0", e.g. 045 instead of 45.
For example, to call Seattle from Ukraine, you'll need to dial: 0 ~ 0 1 206 XXX-XX-XX , where
~ long dial tone
00 - International Call Prefix
1 - USA code
206 - code of Seattle
XXX-XX-XX - telephone number
To call Kiev from abroad you would dial:
International Call Prefix of your country
380 - International code of Ukraine
44 - code of the city (Kiev)
Telephone number