What hidden fees should I watch for in my 401(k)?

Three kinds of fees quietly erode 401(k) balances. First, investment expense ratios — the annual percentage each fund charges; index funds may cost 0.05% while some actively managed or annuity options exceed 1%. Second, administrative fees for recordkeeping and plan management, sometimes charged as a flat dollar amount or a percentage of assets. Third, individual service fees for things like loans or advice. A seemingly small 1% annual drag can cost you tens of thousands of dollars over a career because it compounds against your growth. Your plan must send an annual fee disclosure (a 404(a)(5) statement) listing every charge — read it. Favor the lowest-cost index options, and if your plan's fees are high across the board, prioritize an IRA for additional savings after capturing the employer match. Small percentage differences become huge over 30 years.