Competition from web powerhouses like Alibaba.com and AmazonSupply.com, and a shift away from electronic data interchange, are among the main trends behind growth in business-to-business e-commerce that will push B2B online sales to about $6.7 trillion by 2020, research and advisory firm Frost & Sullivan says.

The firm projects B2B online sales in the United States will reach $1.9 trillion by 2020, and that B2B online sales in China will reach $2.1 trillion. It didn’t break out figures for other countries.

“The main drivers for migration to B2B is the pressure from industry leaders to move to online platforms,” says Archana Vidyasekar, senior research analyst in Frost & Sullivan’s Visionary Research Group, which conducted the December 2014 study, “Future of B2B Online Retailing.”

Frost & Sullivan defines B2B e-commerce as all sales transactions between businesses—including manufacturers and wholesalers, and wholesalers and retailers—conducted primarily through the Internet, including via mobile commerce. It figures its estimate of $6.7 trillion in global online B2B sales will account for 27% of total B2B sales of $25 trillion in 2020.

Vidyasekar also points to other reasons behind the expected growth in B2B e-commerce, including the trend for more companies to participate in “many-to-many” e-marketplaces, with large numbers of both buyers and sellers, such as Alibaba.com and AmazonSupply.com.

Other trends she cites as behind the growth include:

an expectation among a growing number of companies that they will be able to buy and sell online;

some companies shifting to procurement through the Internet instead of through electronic data interchange, or EDI;

the growing interest of companies in placing orders through mobile devices.

In a related report, Frost & Sullivan cited the combined industries of B2B and retail e-commerce as the most significant of several emerging industries judged by their market attractiveness, ability to disrupt their industry, level of certainty of future business, and degree of innovation.

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