Southeast Asia's (SEA) mobile users are expected to hit 453.3 million subscribers by the close of this year, growing 18.4 percent over 2008. Billings are estimated to grow by 13.6 percent year-on-year to top US$32 billion by year-end.

New analysis from Frost & Sullivan, 2009 Southeast Asia Wireless Outlook, finds that the mobile subscriber base in the region - covering seven Southeast Asian nations - grew 36 percent year-on-year to reach 383 million users in 2008, for a corresponding mobile penetration of 72.5 percent. By the close of year 2014, Frost & Sullivan estimates SEA's mobile subscribers to reach 606 million, growing at a CAGR (compound annual growth rate) of eight percent (2009-2014).

SEA's mobile services grossed an estimated US$28.3 billion in revenues in 2008, and are forecasted to reach billings of US$36.2 billion by end-2014, at a CAGR of 4.2 percent (2009-2014).

The diversity of SEA markets means that growth will be driven by a mix of subscriber net additions of consumers in the rural districts - many of whom will receive mobile connectivity for the first time as networks continue to expand beyond major urban areas - as well as the increase in data usage and higher-end services brought on by 3G.

Frost & Sullivan industry analyst Shaker Amin explains, "In saturated markets like Singapore and Malaysia with mobile penetration already at 131 percent and 97.8 percent respectively, growth, although marginal, will largely be fuelled by user migration to 3G, mobile broadband uptake and generally, the higher consumer appetite for mobile content and data services.

"On the other extreme, growing markets like Cambodia, Vietnam, Indonesia and the Philippines, with mobile penetration well below 75 percent and even lower fixed broadband penetration, are likely to see growth in new subscriber additions," he says, adding that these users are predominantly low-ARPU (average revenue per user) prepaid subscribers.

Amin believes that mobile usage in these growing markets will continue to be dominated by voice and basic text messaging services. He says, "Although 3G will be making its entry into many of these markets, it will be some years still before 3G services become commonplace."

Only about six percent (22.9 million) of SEA's total mobile users last year were 3G subscribers.

The race to roll-out 3G services in the hugely competitive growing markets however shows no signs of abating. Cambodia, Indonesia, Thailand and Vietnam - each have no less than six mobile operators; Indonesia the most with eleven. "As operators compete fiercely to enrol new subscribers, 3G will be the technology to eventually deliver [mobile] broadband to the rural communities that are not likely to ever receive fixed broadband access," Amin adds.

In 2008, SEA accounted for approximately 21.5 percent of the total mobile users in Asia-Pacific (18 countries).