One issue that's almost always overlooked in assessing the value and the rewards of a 401(k) plan are the administrative fees that the plan charges its participants. The largest enemies to your long-term savings through a 401(k) plan are excessive fees by the selected mutual funds. Another set of fees also is circling around your retirement funds, nibbling away at your savings and nearly invisible to the naked eye. These are the fees associated with running the 401(k) plan itself.

Participants in 401(k) plans are currently not adequately informed about the fees associated with the day-to-day operational costs of running increasingly more complex plans. These fees include the costs of mailings and other record-keeping, telephone voice response systems, daily valuation services, educational seminars, retirement-planning software -- and all the rest of the clutter.

For instance, some 401(k) plans allow participants to change their asset allocations every day if they so desire -- i.e., switching between different mutual funds however much they want. Other plans allow changes only every three months. Since providing any service, regardless of whether it is really something that the participants would want, exacts a price, there are real costs to providing every service in a 401(k) plan.

If you have the opportunity to help your office select a plan provider, it is well worth keeping in mind that having too many mutual fund choices is a cost, not a benefit. Similarly, the opportunity to move money into, out of, and between different funds is also a cost, not a benefit. The simpler the plan is, the less it will cost to maintain.

Until recently, the administrative costs were generally assumed by the employer. Now, according to the Department of Labor, there has been evidence of a trend to shift expenses to plan participants. While these plan administration expenses are generally not too high (generally less than 0.5% of assets), they are growing, and participants should keep an eye on them. Further information on the subject is available from the Department of Labor, which offers a handy checklist of questions to ask in order to gather information about the fees and expenses paid by your plan:

To learn more about how to maximize a 401(k) plan, visit our 401(k) Center, and consider taking a free trial of Motley Fool Rule Your Retirement. Or drop by our Foolish 401(k)s discussion board -- where folks will be happy to answer your questions. We're currently offering a free trial of our entire discussion board community.

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