Every two weeks, millions of American workers deposit a paycheck that is smaller than it needs to be. Not because their employer is underpaying them, but because they are not contributing enough to their 401(k) to collect the full employer match. The money their company has agreed to put into their retirement account simply never gets contributed.
Research from the National Bureau of Economic Research found that roughly half of employees in the plans studied contributed below the level needed to capture their full employer match. A Financial Engines analysis, reported by CBS News, estimated the collective cost at $24 billion a year in unclaimed matching contributions across the U.S. workforce. That study, conducted in the mid-2010s, has not been replicated with newer data, but the structural conditions that produced the gap have not fundamentally changed. A separate breakdown published by Money magazine placed the average individual shortfall at roughly $1,336 per year and projected that, compounded over 20 years at a typical market return, the lost wealth could reach approximately $42,855 per worker.
The actual dollar amount left behind varies by salary and plan design. Consider a worker earning $65,000 whose employer offers a dollar-for-dollar match up to 5 percent of pay. If that worker contributes only the 3 percent default rate common at many companies, they collect $1,950 in matching funds but leave $1,300 unclaimed. At a salary of $75,000 with the same formula, the gap widens to $1,500. Across a range of typical salaries and match structures, the average unclaimed amount lands in the neighborhood of $1,750 a year. Exposed to decades of compound growth, that annual shortfall can quietly erase tens of thousands of dollars from a retirement nest egg.
Not every study agrees on the exact share of workers affected. Vanguard’s annual “How America Saves” report has put the share of workers missing part of their match closer to one in three rather than one in two, likely reflecting differences in the populations and plan designs studied. But even the lower estimate means millions of participants are walking past employer dollars every pay period.
Why the default rate is the biggest culprit
The gap between what workers contribute and what they need to contribute is not random. A Bureau of Labor Statistics analysis of automatic enrollment and employer match rates identified a structural mismatch baked into plan design: many companies auto-enroll workers at 3 percent of pay, but their match formulas require contributions of 5 or 6 percent to unlock the full employer contribution. That two- or three-percentage-point gap is where most of the unclaimed money lives.
Behavioral economists James Choi, David Laibson, and Brigitte Madrian documented the pattern in a series of NBER papers, including one informally known as “$100 Bills on the Sidewalk” (NBER Working Paper No. 11554). Their research showed that inertia is remarkably powerful: once workers land at a default contribution rate, most never change it, even when doing so would deliver what amounts to an immediate, guaranteed return on their money. A companion paper (NBER Working Paper No. 13352) found that auto-enrollment successfully pulls more people into 401(k) plans but often parks them at a savings rate too low to capture the full match.
The SECURE 2.0 Act, signed in late 2022, attempted to close this gap. New 401(k) and 403(b) plans established after December 29, 2022, must auto-enroll eligible employees at a contribution rate of at least 3 percent, with automatic annual escalation of 1 percentage point per year until the rate reaches at least 10 percent (and no more than 15 percent). As of mid-2026, those escalation provisions are now in effect for qualifying new plans, and over time they should push more workers past the match threshold. But the mandate applies only to new plans. Existing plans, which cover the vast majority of current participants, are not required to adopt auto-escalation, though many employers have voluntarily added the feature.
It’s not always a mistake
Calling every uncaptured match dollar a blunder oversimplifies the picture. A peer-reviewed study published in Economics Letters found that liquidity constraints, meaning day-to-day cash needs like rent, medical bills, and debt payments, explain a significant share of the shortfall even when the match incentive is economically attractive. For a worker living paycheck to paycheck, diverting an extra 2 percent of gross pay into a retirement account they cannot touch until age 59½ may not be realistic, no matter how favorable the long-term math.
Lower-income workers, younger employees early in their careers, and those with irregular hours or unstable earnings face the sharpest version of this trade-off. The U.S. Department of Labor notes that retirement savings decisions sit within the broader context of wages, household expenses, and competing financial obligations. Policy solutions that only nudge contribution rates upward without addressing income volatility or emergency savings will help some workers but not all.
Vesting: the other way match money disappears
Even workers who contribute enough to earn the full match can lose some or all of it if they leave their job before the employer’s vesting schedule is satisfied. Vesting determines how much of the employer’s contributions a worker actually owns. Some plans vest immediately, meaning every matched dollar belongs to the employee from day one. Others use a graded schedule, where ownership increases over three to six years, or a cliff schedule, where the worker gets nothing until a set number of years have passed and then becomes fully vested all at once.
According to the Bureau of Labor Statistics, graded and cliff vesting schedules remain common, particularly at larger employers. Workers who change jobs frequently, especially early in their careers, may forfeit matched contributions they assumed were theirs. Checking your plan’s vesting schedule is just as important as checking the match formula itself.
How to figure out what you’re leaving behind
For workers who do have room in their budgets, the first step is straightforward: find your plan’s match formula. It is typically listed in the Summary Plan Description, available through your employer’s HR portal or benefits website. Common structures include a dollar-for-dollar match on the first 3 to 6 percent of salary, or a 50-cents-on-the-dollar match on a higher percentage. The difference matters. A 50 percent match on up to 6 percent of pay means you need to contribute 6 percent to get a 3 percent employer contribution, while a 100 percent match on up to 3 percent requires only a 3 percent contribution to capture the full benefit.
Once you know the formula, compare it to your current contribution rate. Most plan providers, including Fidelity, Vanguard, and Schwab, display both your contribution percentage and your employer’s matching contributions on your online dashboard. If there is a gap, you can usually adjust your deferral rate in minutes through the same portal.
Workers who cannot close the gap all at once can use a staircase approach: increase contributions by 1 percentage point now, then add another point each time you receive a raise or pay off a recurring bill. Many plans also offer an auto-escalation feature that does this automatically on an annual schedule. Opting in removes the need to remember, which directly counters the inertia researchers have identified as the primary barrier.
One detail worth noting: because 401(k) contributions are made with pre-tax dollars in a traditional plan, the hit to your take-home pay is smaller than the contribution itself. A worker in the 22 percent federal tax bracket who increases their contribution by $100 per month sees their paycheck shrink by roughly $78, not $100. The tax savings soften the adjustment more than many people expect.
Why a 1 percent increase carries outsized weight
Even a partial increase matters more than it might seem. A worker who moves from a 3 percent contribution to 4 percent on a $50,000 salary captures an additional $500 in annual employer matching (assuming a dollar-for-dollar match). That $500, invested each year and compounded at a 7 percent average annual return, could grow to more than $20,000 over 20 years. The required reduction in take-home pay is roughly $32 per month after accounting for the tax benefit in the 22 percent bracket. Few other financial moves available to most households offer a comparable return for that level of sacrifice.
The scale of unclaimed match money across the country may shift as SECURE 2.0 auto-escalation provisions take hold in newer plans and as more employers voluntarily adopt the feature. But for the tens of millions of workers in existing plans right now, the match formula on their latest benefits statement is the number worth checking first. The money is already budgeted by the employer. Whether it ends up in the worker’s retirement account or never gets contributed at all comes down to a single setting on a benefits portal that takes less than five minutes to change.
David M. Keller is a finance writer based in Columbus, Ohio, covering personal finance and consumer-focused economic topics. He earned his degree in journalism from Ohio University and began his career reporting on local business and economic trends for a regional media outlet. Since then, he has contributed to a variety of online publications, focusing on clear, practical coverage of topics such as cost of living, debt, and everyday financial decision-making.
