“What fees am I paying in my 401(k)?”

Almost certainly some — most people just never see them, because they're taken out of returns rather than billed to you.

There are usually two layers. Fund fees (the "expense ratio") are charged by each investment you hold, expressed as a percentage — the difference between 0.05% and 1% compounds into serious money over a career. Plan administration fees cover running the plan itself; sometimes the employer pays them, sometimes participants do.

Where to look: your plan is required to disclose fees in a document (often called a 404(a)(5) fee disclosure or just the fee disclosure notice), and each fund's expense ratio is listed right in your plan's investment menu.

You usually can't change what the plan charges — but you often *can* choose lower-cost funds within the same menu, and knowing the number is the first step to caring about it.