The greatest enemies to your long-term savings through a 401(k) plan are excessive fees. Right now, they're circling your retirement funds, nibbling away at your savings.

Participants in 401(k) plans are not adequately informed about the fees associated with the day-to-day 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 only allow changes every three months. The provision of any service, regardless of whether it is something that the participants would want, exacts a price.

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, however, 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 Retirement area. Or drop by our Foolish 401(k)s discussion board -- where folks will be happy to answer your questions.