Picking 401(k) funds
when you have no idea.

READ3 min · UPDATED
Reviewed against primary sources cited at the bottom of this page.

Your 401(k) has 20 fund options. You have no idea what they mean. Here's the simple process for picking the right one in under 10 minutes.

This page covers US employer-sponsored 401(k) and 403(b) plans. Similar logic applies to other national defined-contribution plans.
THE SHORT VERSION

Look for the lowest-cost S&P 500 or total market index fund in your plan. If you can't find one or don't want to choose, pick the target date fund closest to your retirement year. That's it. The rest is noise.

The overwhelm is normal

Your 401(k) probably shows something like this:

FUND NAME EXPENSE RATIO
American Funds Growth Fund of America0.65%
Vanguard 500 Index Fund0.04%
Fidelity Contrafund0.86%
PIMCO Total Return Bond0.71%
Vanguard Target Retirement 20550.09%
JP Morgan Mid Cap Value1.20%
...and 15 more

Most of these are actively managed funds that charge high fees and underperform their benchmark over 10 years ×DON'T TRUST, VERIFYClaim: A majority of actively managed US equity funds underperform their benchmark index over rolling 10-year windows.Verify at: S&P SPIVA scorecard ↗SPIVA publishes the active-vs-passive scorecard quarterly.. You don't need to understand all of them. You need to find one.

The decision tree

STEP 1: LOOK FOR AN INDEX FUND

Find any fund with one of these words in its name:

  • "Index"
  • "S&P 500"
  • "Total Market"
  • "500"

These are passively managed funds that track the market rather than trying to beat it.

STEP 2: CHECK THE EXPENSE RATIO

The expense ratio is the annual fee as a percentage of your investment. It appears as "0.04%" or "0.65%" or sometimes "4 bps" (4 basis points).

  • Under 0.20 percent: good
  • Under 0.10 percent: great
  • Over 0.50 percent: high, look for better
STEP 3: PICK THE CHEAPEST INDEX FUND

Choose the cheapest S&P 500 or total market index fund you found. This is your selection.

If you find multiple index funds:

  • Total market fund: holds all US stocks (preferred).
  • S&P 500 fund: holds the 500 largest US stocks (nearly identical outcome).
  • Choose the cheaper one.
STEP 3 ALTERNATIVE: NO INDEX FUND IN YOUR PLAN

If your plan has no index fund, pick the target date fund closest to your retirement year. This is a fine default: slightly higher cost than building your own allocation but hands-off and appropriate. See Target Date Funds.

What to ignore

  • Actively managed funds with high expense ratios. Ignore.
  • "Guaranteed" or "stable value" funds. For retirement savings, these typically return less than inflation over long periods. Not appropriate for someone 20 to 40 years from retirement.
  • Bond funds if you're under 50. Not strictly necessary. Time is your volatility buffer. Bonds add stability at the cost of return.
  • Anything with a sales load (front-end or back-end), a fee paid when you buy or sell. Avoid.

The contribution percentage

Once you've picked the fund, set your contribution to at least capture the full employer match.

How to find your match: HR department or benefits portal. Example: "3 percent match at 100 percent" means if you contribute 3 percent of your salary, your employer adds 3 percent.

Minimum contribution to capture the full match: whatever that match requires, usually 3 to 6 percent.

PAINLESS CONTRIBUTION ESCALATOR

After capturing the match, increase your contribution by 1 percent every time you get a raise. You never feel the reduction in take-home because it's absorbed by the raise. See Paycheck Optimizer.

Last updated 2026-04-23. Not financial advice.

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