The average person pays about $250 a year in 401(k) fees, according to Investment Company Institute, which would cost a dual-income household $20,000 over 40 years. A survey by the Transamerica Center for Retirement Studies found that 71% of employees were not aware that 401(k)s even had fees. There are a few suggestions workers can use to avoid hidden 401(k) fees. Some of the 401(k) fees come from managing the fund, but the costs on index funds are a fraction of 401(k) costs. IRAs can be an alternative investment vehicle, unless the 401(k) offers matching contributions. Insurance-based products like variable annuities may charge 401(k) participants 2% annually. Borrowing from 401(k)s can result in service fees. Employers can look into a plan's fee and try to get better options.