Nearly 80 percent of companies with 100 or more employees are overpaying on 401(k) and 403(b) plan administrative fees, according to findings from Abernathy Daley 401k Consultants, a consultancy in 401(k) plan administration and employee education. This finding suggests that many companies are not benefiting from an independent benchmark of their corporate retirement plans, failing to capitalize on fee reductions over the past three years.

Along with concerns about overpayment, the lack of realignment with best practices in fees indicates that companies overall are not conducting regular compliance-related benchmarking of their retirement plans, opening the door to risks.

Benchmarking audits "compare the fees, administrative services, and investment offerings of a company's plan to industry standards," said Steven Abernathy, principal and chairman of Abernathy Daley 401K Consultants. "The goal is to ensure that the plan is competitively priced, adheres to best practices, and aligns with fiduciary responsibilities.