Nearly 875,000 employees increased their contributions to 401k plans in 2010, a 21% increase over 2009’s level of 721,000 employees, according to BofA/Merrill Lynch’s Retirement & Benefit Plan Services report. The quarterly report tracks plan participation within BofA/Merrill’s proprietary 401k business, which oversees about 1.5 million people and $92.1 billion in total plan assets.

Some of the specific findings include: a 7% increase in the use of automatic enrollment, with more than 250 plans with this feature; a 23% increase in the use of automatic increase, with more than 140 plans now using it; and a 23% increase in plan sponsor adoption of the advice access service.

The Financial Wellness Monitor, a feature introduced in February 2010, has been adopted by more than 400 plans. This enables plan sponsors to identify segments of employees who are not exhibiting the saving behaviors that would lead to a successful retirement. With this system, each participant is assigned a score from zero to 10, with 10 being the best. Points are deducted for risky behaviors.

The report also noted the importance of allowing employees to manage their retirement benefits in connection with their health care enrollment periods. When employers offer an easy “one-click” option to make changes to 401 plans during an annual health care benefit process, it drives a significant increase in participation, the report said.

Indeed, the issue of the role of health care in retirement came up in a meeting with reporters earlier in the week when Merrill unveiled its Affluent Insights Quarterly. Andy Sieg, Head of Retirement Services, highlighted health care expenses, among other topics, saying that planning for your wealth, and planning for your health, are “two sides of the same coin.”