What 60 Percent of 401(k) Money in Default Funds Tells You

In the average American 401(k) account, approximately 60 percent of contributions flow into target-date funds. Target-date funds (TDFs) are the most common default investment option for 401(k) participants who do not actively select their own portfolio. The funds automatically adjust their asset allocation based on the participant's expected retirement year, gradually shifting from equity-heavy holdings in early career years to bond-heavy holdings as retirement approaches. The widespread adoption of TDFs represents one of the most consequential financial-product trends of the past 25 years, and it has implications for American retirement readiness that are still being assessed.

The Origin and Adoption. Target-date funds emerged in the mid-1990s but became substantially more important after the 2006 Pension Protection Act, which gave employers safe-harbor protection when defaulting employees into qualified default investment alternatives (QDIAs). The 2006 legislation effectively encouraged employers to use TDFs as the default option for new 401(k) participants. By 2010, most major retirement plans were using TDFs as the default. By 2020, TDFs held over 3.5 trillion dollars in assets across various plans. By 2024, the figure had grown to over 5 trillion.

The adoption rate of TDFs has been remarkable. Approximately 70 percent of 401(k) participants now hold at least some TDF assets. For participants under 40, the percentage is closer to 85 percent. The default-investment status of TDFs means that the typical American retirement saver does not actively select investments — the TDF chooses for them.

The Glide Path Discipline. TDFs work through a "glide path" — a pre-determined asset allocation that shifts over time. A typical 2050 target-date fund might hold 90 percent equities and 10 percent bonds in 2024 (when participants are roughly 25-35 years from retirement). By 2040, the same fund would hold approximately 60 percent equities and 40 percent bonds. By 2050 (the target retirement date), it would hold roughly 40-50 percent equities and 50-60 percent bonds. The glide path provides automatic rebalancing without participant action.

This automatic rebalancing addresses one of the most common retirement-saving failures: participants who fail to adjust their portfolio risk as they approach retirement. Without TDFs, many participants would maintain aggressive equity allocations close to retirement, creating substantial volatility risk. With TDFs, the rebalancing happens automatically.

The Implementation Variations. Different fund managers implement TDFs differently. Vanguard's target-date funds use predominantly index-fund holdings with relatively low expense ratios. Fidelity uses more actively managed underlying funds. T. Rowe Price emphasizes equity exposure throughout the glide path. American Funds (Capital Group) uses an active-management approach with somewhat different glide-path mechanics.

These variations matter for performance. Over multi-decade periods, expense ratios compound substantially. A 0.10 percent expense ratio (Vanguard) versus a 0.50 percent expense ratio (some actively managed alternatives) produces a 25-30 percent difference in cumulative wealth over 30 years. Most plan participants do not actively choose their TDF — they hold whatever the plan administrator has designated as the default.

The Behavioral Implications. What's interesting about TDF adoption is the behavioral change it has produced. Participants in TDF plans typically save more than participants in plans where they must actively select investments. The reasoning is that the cognitive cost of investment selection (a barrier to plan participation) has been reduced or eliminated. The default-investment provision has effectively lowered the barriers to retirement saving.

The cumulative effect on American retirement-readiness has been positive but not transformative. Average 401(k) balances have grown substantially since 2006, but the median 401(k) balance for workers approaching retirement remains below most retirement-readiness benchmarks. The behavioral lift from TDFs has helped, but has not solved the broader challenge that most Americans are not saving enough for retirement.

The Recent Stress. The 2022 bear market produced an unusual stress on TDFs. The simultaneous decline in both stocks and bonds (the typical TDF holdings) produced cumulative losses that were larger than typical. Many TDF investors saw substantial portfolio drawdowns at exactly the points in their lives when they expected the most stable returns.

For pre-retirees specifically (those within 5-10 years of retirement), the 2022 losses were particularly painful because they affected the portion of the glide path designed to be conservative. The 2022 experience has produced some criticism of TDF design — particularly the higher equity allocations that some funds maintain even close to retirement.

The Larger Pattern. What TDFs represent is one of the most successful applications of behavioral economics to consumer finance. The recognition that most consumers will not actively manage their retirement portfolios led to the design of products that produce reasonable outcomes through default. The cumulative wealth that has accumulated in TDFs (over 5 trillion dollars) reflects the success of this default-engineering approach.

For finance-policy analysts, the TDF experience is one of the cleaner examples of how default settings can shape consumer outcomes at scale. Similar dynamics operate in organ donation registration, insurance enrollment, and various other policy contexts. The lesson is that defaults matter enormously and that designing defaults thoughtfully produces better outcomes than expecting consumers to actively optimize their decisions.

The Larger Lesson. Most Americans are not actively managing their retirement portfolios. They hold whatever their plan administrator has designated as the default investment. This means that the choice of default investment — by plan administrators and by regulators — has more impact on American retirement outcomes than the financial-literacy programs that focus on individual education.

The TDF default has been better than the cash-or-money-market defaults that preceded it (which produced very poor long-term returns). Whether the next generation of default investments improves further — perhaps through more sophisticated risk-management or alternative asset class incorporation — will determine retirement outcomes for the next generation of Americans.

For the typical American 401(k) participant, the practical takeaway is that the choice of TDF (often constrained by what the plan offers) is one of the most important financial decisions they will make, even if they do not actively make it. Reviewing the TDF's expense ratio, glide path, and underlying holdings is worth a few hours of attention even for participants who otherwise prefer to ignore retirement-investment decisions.

Now go enjoy your Saturday. The rebalancing will happen without you.

Sources: - Investment Company Institute (ICI) annual factbook - Plan Sponsor Council of America 401(k) data - Industry coverage: Bloomberg, Pensions & Investments - Various target-date fund prospectuses