Fidelity Investments reported strong sales growth last year of defined contribution plans to small and medium-sized business, the Boston-based retirement services provider reported Thursday.

The company sold more than 1,400 plans with $50 million in retirement assets or less, an estimated 57% increase over the number sold in 2010. Fidelity's 2011 sales commitments represented $6.6 billion in assets, up 40% from a year earlier, company officials said.

Although company officials are reluctant to predict what the increased sale in retirement plans means for the small and mid-sized business market, they say they are optimistic the increase will continue into 2012.

"We are seeing more opportunity to talk with business owners about benefits, which could mean they think the economy is continuing to come around," says Mike Harger, a senior vice president for Fidelity who works with the advisor community. "I do not have numbers for you yet for 2012 but the feeling from plan sponsors is that growth of 2011 will continue."

Investments' Executive Vice President Jeffrey Lagarce attributed the large sales bump to the increase of small and midsize employers and advisors looking for a company with a proven track record providing 401(k) plans.  

Fidelity services approximately 11.6 million 401(k) participants in 20,000 plans and works with both plan sponsors and nearly 3,000 financial advisors. The company had assets under administration of $3.5 trillion, including managed assets of $1.6 trillion, as of January 31.