For the second time in as many years, Charles Schwab took the top ranking among large plan providers in a retirement plan satisfaction survey by J.D. Power.

Schwab scored 821 points out of 1,000, followed by Nationwide with 811 and Bank of America with 809 in the company's U.S. Retirement Plan Participant Satisfaction Study. Vanguard fell out of the top three to a fifth-place ranking.

The survey, in its second year, evaluates participant satisfaction with providers of group retirement plans such as 401(k)s based on six factors: interaction across live and digital channels; investment and service offerings; fees and expenses; plan features; information resources; and communications. Plan providers are ranked in three categories based on their overall mix of business in terms of average plan size. The study is based on the responses of 8,332 retirement plan participants and was conducted in February and March.

In the medium plan segment, the top three providers were Bank of America with 836 points, followed by Fidelity Investments with 814 points and Nationwide with 813 points. 

Fidelity Investment was top in the small plan category with 790 points. Nationwide was second with 789 points and John Hancock Retirement Plan Services followed with 745 points. 

The survey also revealed that retirement plan participants are not confident in their retirement preparedness. Just 17 percent say they feel "very confident," the report said. That number falls to 15 percent among baby boomers. The report suggested that many retirement plan providers need to rethink their approach when it comes to both digital tools and human advisors to build that confidence in participants.