March 2005

28.03.2005
22.03.2005
Financial Results for the Fourth Quarter and Full-Year Ended December 31, 2004

Moscow, Russian Federation — March 22, 2005 — Mobile TeleSystems OJSC (“MTS” — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, today announces its fourth quarter and full-year 20041 financial and operating results.

21.03.2005
18.03.2005
MTS Mobile Phones Now Available at DIXIS

The МТS i42 and МТS i43 mobile phones are now available at DIXIS retail outlets (including St. Petersburg, Ekaterinburg, Nizhny Novgorod, Voronezh and Krasnodar).

16.03.2005
Fourth Quarter and Full Year 2004 Financial Results announcement and conference call

The management of Mobile TeleSystems (MTS) will be holding a conference call to discuss the Company’s Fourth Quarter and Full Year 2004 Financial and Operating Results on Tuesday, March 22, 2005.

11.03.2005
50% SMS Discount for New Super JEANS Users!

50% SMS discount promotion will be prolonged until March 20!

09.03.2005
MTS Announces Subscriber Growth Numbers for February 2005

Moscow, Russian Federation — March 09, 2005 — Mobile TeleSystems OJSC (“MTS” — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, announces that its consolidated subscriber base reached 37.15 million users on February 28, 2005.

04.03.2005
01.03.2005

Contact investor relations:

+ 7 495 223 20 25 ir@mts.ru

MTS Investor Relations
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