Employers are improving access to their 401(k) plans, according to a survey released Wednesday.

The Hewitt Associates Inc. survey of 300 mid- to large-size employers found that 74% of 401(k) plans do not have a service requirement, up from 61% in a comparable survey Hewitt conducted in 2007.

In addition, looking at plans with employer matching contributions, 56% of plans in 2009 did not have any service requirements for participants to receive the match, up from 44% in 2007.

On the other hand, 10% of employers have suspended their matching contributions during the past two years, the survey found.

“Companies’ bottom lines were significantly impacted by the financial crisis in 2008. As the last resort, some had to reduce or suspend their employer contribution to 401(k) plans to make ends meet,” said Pam Hess, Hewitt’s director of retirement research in Lincolnshire, Ill., in statement.

Still, many of those freezes either are or soon will be lifted. “That trend has slowed. In fact, many employers have already indicated their likelihood to reinstate matching contributions in 2010,” Ms. Hess said.

Employers continue to move away from investing matching contributions exclusively in company stock. Just 17% of employers do so, down from 23% in 2007 and 45% in 2001.

That downward trend coincided with the collapse of one-time energy giant Enron Corp. Enron matched employees’ deferrals exclusively with company stock and barred employees until age 50 from divesting those shares, leaving thousands to watch helplessly as the value of their shares plunged to virtually nothing.

The survey found a big increase in the number of employers offering an automatic enrollment feature. Such programs are geared to those employees—typically new hires—who don’t indicate whether they want to enroll in their employer’s 401(k) plan. With automatic enrollment, those employees are enrolled unless they specifically object.

In 2009, 58% of employers offered automatic enrollment, up from 34% in 2007 and 19% in 2005. Of those employers using automatic enrollment, 69% default employees into a target-date fund, up from 50% in 2007.

The funds are so named because the investment mix is adjusted over time, with a more aggressive allocation for funds with retirement target dates further in the future and more conservative asset allocations for retirement dates that are closer.

A summary of the survey, “Trends and Experience in 401(k) Plans,” is available online at www.hewitt.com.