401(k) Statistics (2026)

The 401(k) has become the backbone of American retirement saving. At the end of June 2026, Americans held about $10.8 trillion in 401(k) plans, the largest component of $15.0 trillion in defined-contribution assets and part of a record $51.2 trillion US retirement market (see the chart and table below).

That money sits in roughly 730,000 plans on behalf of about 70 million active participants plus millions of former employees and retirees. Only IRAs, at $19.9 trillion, are a bigger pool, and much of the IRA total is money rolled over out of 401(k)s when people change jobs or retire.

There is a huge gap between the average and the typical 401(k) balance. Vanguard reported an average participant balance of $167,970 at year-end 2025, but the median, the saver right in the middle, was just $44,115. When the average is nearly four times the median, a minority of very large accounts is doing the pulling.

The median is the more honest yardstick for how you compare. It did rise 16% from the prior year on strong markets (the average rose 13%), and Fidelity's separate book showed an average 401(k) balance of $155,800 in Q2 2026, but for most workers the reality is a mid-five-figure balance, not the six-figure average that headlines tend to quote.

401(k) balances build slowly then compound. Savers under 25 average about $7,259 (median $2,234), the 35-44 group averages roughly $120,742, and those 55-64 average about $305,006 as decades of contributions and market gains stack up (see the chart and table below).

Notice how far the median trails the average in every band: even at 55-64 the median is about $107,269, roughly a third of the average. That gap is the clearest evidence that retirement wealth is concentrated, and that many older workers are approaching retirement with far less than the averages suggest.

Contribution rates are at record highs. Vanguard participants deferred an average of 7.6% of pay in 2025 (median 6.6%), and Fidelity's larger book showed a record 9.6% average employee deferral in Q2 2026. Add the employer contribution and Fidelity's total 401(k) savings rate held at a record 14.4%, the closest it has ever been to the 15% rule of thumb (see the chart below).

Automatic escalation is quietly doing much of the work: about 31% of participants had their deferral bumped up by an automatic annual increase, and 45% raised their savings rate in total. Small, automatic nudges compound into meaningfully higher lifetime contributions.

The match is the closest thing to free money in personal finance, and most plans offer one. Vanguard puts the average employer-promised match at 4.7% of pay in 2025 (median 4.0%), while Fidelity's data shows an average employer contribution of 4.8%, worth roughly $2,080 per participant per quarter (see the table above).

A common formula is 50 cents on the dollar up to 6% of pay, meaning a full 3% match if you contribute 6%. Not capturing the full match leaves guaranteed return on the table, which is why advisers say to contribute at least enough to get every matched dollar before anything else.

Seven-figure 401(k)s are still rare but growing fast. The number of Fidelity 401(k) millionaires climbed to about 665,000 in the fourth quarter of 2025 (Fidelity's most recent published count), up from 654,000 the prior quarter, as three straight years of double-digit balance gains lifted long-tenured savers over the line.

The engine is time, not timing. Savers who stayed in the same 401(k) for 15 continuous years averaged $558,300, and the average for women 15-year savers crossed half a million dollars ($501,100) for the first time. Consistency and compounding, not stock-picking, build these balances.

Not everyone can save in a 401(k) at work. As of March 2026, retirement benefits were available to 72% of private-industry workers and 70% had access to a defined-contribution plan, but only 62% of full-time workers and 20% of part-time workers actually participated in a plan (see the table below).

Access is deeply unequal. About 91% of workers at firms with 500 or more employees have a plan, versus just 59% at firms with fewer than 100. Part-time workers fare worst of all, with 44% access. That coverage gap, tens of millions of workers with no workplace plan, is the central weakness of the US system.

There is a difference between being offered a plan and being in it. In the private sector, 70% of workers have access to a defined-contribution plan but only 49% participate (March 2026), a take-up gap driven by lower-wage and younger workers who often opt out or never enroll.

This is exactly why automatic enrollment matters so much: when the default is being signed up, participation jumps well above 90% (94% in Vanguard's auto-enrollment plans versus 64% under voluntary enrollment in 2025). The workers most likely to skip a plan are the ones automatic features help the most, which is why plan design has become the policy lever of choice.

Plan design, not willpower, explains most of the improvement in retirement saving. The share of Vanguard plans with automatic enrollment has grown from 10% in 2006 to 61% in 2025, flipping the decision from opt-in to opt-out and lifting plan-weighted participation to a record 86% in Vanguard's book.

Auto-enrollment is usually paired with auto-escalation, which nudges the deferral rate up a point a year. Together they turn inertia, historically the enemy of saving, into a tailwind: doing nothing now means staying enrolled and gradually saving more.

The typical 401(k) is far more diversified than it used to be, thanks to target-date funds. About 69% of Vanguard participants were in a professionally managed allocation at year-end 2025, most (61%) in a single target-date fund, up from a world where people picked funds (often badly) on their own (see the table below).

At the asset level, mutual funds hold about $6.2 trillion, or 58%, of 401(k) money as of June 2026, with $3.7 trillion in equity funds and $1.7 trillion in hybrid and target-date funds. The shift to one-decision, age-appropriate portfolios has quietly reduced the behavioral mistakes that used to plague self-directed accounts.

401(k) investing has gotten dramatically cheaper. The average equity mutual fund expense ratio paid by 401(k) participants fell to 0.26% in 2024, down 66% from 0.76% in 2000 and well below the 0.40% paid by fund investors industrywide (ICI, flagged as 2024 research).

Lower fees compound just like returns, in reverse: shaving half a percentage point off costs over a career can add tens of thousands of dollars to a final balance. Scale, index funds, and fee competition among recordkeepers have all pushed costs toward historic lows.

The 401(k) is a leaky bucket for some savers. In 2025, 13% of Vanguard participants in plans offering loans had one outstanding, and 6% of those offered hardship withdrawals took one, up from 5% in 2024 and 2% in 2021, a sign of financial strain even as balances hit records (Vanguard, How America Saves 2026).

Loans and hardship withdrawals dent long-term growth because the money stops compounding, and a loan can trigger taxes and penalties if you leave your job before repaying. Used sparingly they are a safety valve; used often they undermine the whole point of the account.

The IRS raised the 401(k) limits for 2026. The employee elective-deferral cap rose to $24,500, up from $23,500, with an $8,000 catch-up for those 50 and older (a $32,500 total) and a new $11,250 super catch-up for ages 60-63 under SECURE 2.0, bringing their total to $35,750 (see the table below).

One change to watch: starting in 2026, workers who earned more than $150,000 the prior year must make their catch-up contributions as after-tax Roth dollars. The total that can flow into an account from all sources (employee plus employer) rose to $72,000.

The data points to a few durable lessons. Contribute at least enough to capture the full employer match, aim toward the 15% total savings rate that top savers hit, and let a low-cost target-date fund handle the allocation so you avoid the behavioral mistakes that hurt self-directed investors.

The bigger takeaway is that time and consistency, not clever trades, build these balances: the millionaires and half-million-dollar savers are overwhelmingly people who stayed invested for 15-plus years. If your median-sized balance looks small today, steady contributions and compounding are what close the gap.