RIM’s BlackBerry dominates smartphone market share—at 37%—among all sizes of US businesses, while Microsoft’s Windows Mobile platform comes in second—at 26%—according to the Strategy Analytics Wireless Enterprise Strategies service report, “Smartphones for Business: US Carrier & Platform Choice.”

Among the companies surveyed, Verizon Wireless and AT&T dominated business subscriptions, with AT&T slightly ahead in large enterprises (1000+), while Verizon showed greater penetration among small companies (under 100). Employees of large enterprises were also the most loyal BlackBerry users. This report also highlights that Symbian, Google Android and Apple’s iPhone are not serious contenders for US Business use.

“This research shows that the US market is consolidating, with many companies working primarily with AT&T, Verizon and, to a lesser extent, Sprint Nextel. RIM is clearly the leading smartphone business player, followed by Microsoft. What also emerges is that RIM customers expressed a lower willingness to churn than those on other platforms,” commented Andrew Brown, Director of Wireless Enterprise Strategies and author of the report.