Region is expected to double subscriber numbers to 67 million by 2011.
Kenya, Tanzania and the Democratic Republic of Congo (DRC) accounted for over 50% of the mobile telephone market in the East and Central Africa region, according to research by Informa Telecoms and Media.
The report projects substantial growth in the number of subscribers in the region and places each of the respective countries within the top 10 African markets. This is expected to push up the Central and East Africa's share in overall African mobile telephony to 20% in 2011 from the 16% in 2006.
Informa predicts that East and Central Africa's mobile phone subscribers will more than double to 67 million by the end of 2011, up from over 30 million at year-end 2006.
The number of users in Kenya is projected to grow by 87% over the next five years. In the same period, Tanzanian users are expected to grow by 109% while those in DRC will grow by 200%.
These figures put East and Central Africa's mobile penetration growth rate well ahead of the rest of the continent whose average growth is estimated at 72%.
Mobile users account for 83% of Africa's telephony subscribers, a higher proportion than any other region in the world. Mobile network coverage in Africa stands at around 15% and is still the lowest in the world, with penetration rates varying from 72% in South Africa to 1% in Eritrea.
Figures published by the International Telecommunications Union show that mobile subscriber numbers on the continent grew from 15.6 million in 2000 to 135 million in 2005.
The exponential rise in mobile phone penetration in East Africa has led to intense competition among mobile operators, with MTN Uganda, Vodacom Tanzania and Celtel all having slashed international roaming fees throughout 2006 as competition in the region intensifies significantly.