Roughly 6.1 million people are now enrolled in these accounts, first introduced in 2004, according to a new census released Wednesday, April 30, by America’s Health Insurance Plans’ Center for Policy and Research. That’s a 35 percent increase from last year, and nearly double the number of people who were enrolled in HSAs in 2006.

Karen Ignagni, president and CEO of AHIP, said that more large employers are “taking a portfolio approach” to health care coverage, and offering their workers multiple choices for health care, including HSAs. At the same time, more large health plans are including HSAs in their coverage options, with both factors prompting the uptick in enrollment numbers.

Through large employers, specifically, there are currently 2.8 million people using HSAs, or roughly 45 percent of the total number of enrolled individuals. The enrollment rate at large employers is up by 37 percent over last year, according to the census.

“It certainly appears as though we’re at a tipping point right now,” said Ignagni, noting that there were only about 1 million people enrolled in HSAs in March 2005. “Large employers are giving their workforces more choices, and a growing number of individuals are clearly deciding that HSAs suit many of their needs for health care coverage.”

Ignagni also pointed out that individuals enrolled in HSAs are actively using them to pay for their health care costs: The average HSA balance of enrolled individuals in 2007 was $1,380, while the average amount spent last year was $1,080.

Filed by Mark Bruno of Financial Week, a sister publication of Workforce Management. To comment, e-mail editors@workforce.com.