A $1 Million 401(k) Is Really Worth About $760,000 After Taxes. Here’s the Math Retirees Miss.

The $1 million 401(k) has become the default milestone for a comfortable retirement, showing up on projection calculators, in headlines, and in the mental math of anyone tracking a balance. The problem with that milestone is structural: traditional 401(k) balances sit in pre-tax dollars. Every withdrawal gets taxed as ordinary income, which means the number on the statement meaningfully overstates what a retiree actually gets to spend.

A useful working figure: a $1 million pre-tax balance translates to roughly $760,000 of after-tax purchasing power across a full retirement drawdown. That estimate assumes a blended effective federal rate in the low-to-mid-20s throughout the drawdown, plus a modest state income tax layer. The precise number shifts with withdrawal pace, filing status, and the presence of other income sources such as Social Security or a pension.

How the Tax Math Actually Works

Every dollar pulled from a traditional 401(k) is taxed at ordinary income rates. The key distinction retirees often miss: your marginal rate (the rate on your last dollar of income) is not your effective rate (the blended average across all brackets). Understanding that gap changes how you plan withdrawals.

The 2026 federal brackets, set by the IRS under the One Big Beautiful Bill (signed July 4, 2025), run from 10% on the first $12,400 of a single filer’s taxable income up to 37% above $640,600. Married couples filing jointly hit the top bracket above $768,600. The 2026 standard deduction is $16,100 for single filers and $32,200 for joint filers, giving retirees a meaningful first layer of tax-free income before rates begin to apply.

For a retiree drawing $40,000 a year from a $1 million balance under the 4% rule, with a Social Security check on top, most withdrawals land in the 12% and 22% brackets. Effective federal rates typically settle in the mid-teens. Adding state income tax in higher-rate states like California, New York, or Oregon pushes blended effective rates into the low-to-mid-20s across a full retirement. One additional benefit worth noting: the One Big Beautiful Bill gives taxpayers age 65 and older an extra $6,000 deduction on top of the standard deduction for tax years 2025 through 2028, subject to income phaseouts. For those who qualify, it can meaningfully reduce the effective rate during the early drawdown years.

Across a 25-year drawdown, the combined federal and state tax bill on a $1 million traditional balance often totals $200,000 to $250,000. That accumulated liability is where the $760,000 net figure originates.

Inflation Takes Another Bite

Taxes account for roughly half of the erosion, but inflation quietly handles the rest. The Consumer Price Index for All Urban Consumers reached 333.918 in July 2026, up 3.4% over the prior 12 months, according to the Bureau of Labor Statistics. The Social Security COLA for 2026 was set at 2.8%, tied to CPI-W, lifting the average monthly retirement benefit to roughly $2,071. That nominal gain, though welcome, still trails the broader CPI reading, meaning retirees who depend heavily on Social Security have watched purchasing power erode even as their nominal checks grew.

401(k) balances are quoted in nominal dollars. A $760,000 after-tax pool today buys less than the same figure would have bought five years ago, and the gap compounds with each passing year. Across a 25 to 30-year retirement, 2% to 3% annual inflation reduces real purchasing power by roughly a third to a half. Over a long drawdown, that slow grind can ultimately dwarf even the tax hit.

Why $1 Million Is Rare Anyway

The base number is hard to reach in the first place. The personal savings rate stood at 3.9% in Q1 2026, down sharply from 6.2% in Q1 2024, according to the Bureau of Economic Analysis. With Americans spending roughly 96 cents of every dollar they earn, building a seven-figure account requires either a high income, a very long career of consistent contributions, or both.

Vanguard’s “How America Saves 2026” report, covering year-end 2025 data across nearly 5 million participant accounts, puts the median 401(k) balance at $44,115 and the average at $167,970. Both are record highs, yet both sit far short of a million dollars. Fidelity’s Q4 2025 data tell a similar story: the median balance was $34,400 and just 665,000 accounts across its platform carried a balance of $1 million or more. For additional context, Northwestern Mutual’s 2026 Planning and Progress Study found that Americans now believe they need $1.46 million to retire comfortably, a threshold that makes the median balance look more distant still. The million-dollar account is a top-decile outcome, and even that outcome loses roughly a quarter of its face value once withdrawals begin.

What Retirees Can Do About the Gap

Several approaches address the gap between statement value and spendable value:

1. Roth conversions before RMDs begin. Converting portions of a traditional 401(k) or IRA to a Roth in the low-income years between retirement and age 73 fills the 12% and 22% brackets at known rates. The converted balance grows tax-free and avoids required minimum distributions.
2. Withdrawal sequencing across account types. Drawing from taxable brokerage accounts first, at long-term capital gains rates of 0%, 15%, or 20%, and leaving Roth accounts for last stretches tax-advantaged growth and controls the effective rate on 401(k) draws.
3. The standard deduction functions as a zero bracket. The first $16,100 of a single filer’s income (or $32,200 for joint filers) in 2026 is taxed at zero. Structuring withdrawals to fill that zero bracket every year, even if the money is reinvested in a taxable account, captures a rate advantage that otherwise expires unused.

The $1 million balance is a real figure, and the roughly $240,000 in taxes and inflation-driven erosion is baked into that amount. Planning around the net figure rather than the gross aligns expectations with what is actually available to fund retirement spending.

Editor’s note: This update corrects the married filing jointly top-bracket threshold to $768,600 per IRS Rev. Proc. 2025-32 as cited by the Tax Foundation, updates the Vanguard participant count to nearly 5 million per the official “How America Saves 2026” preview, revises the Q1 2026 personal savings rate to 3.9% per the Bureau of Economic Analysis June 2026 revision, adds the average Social Security monthly benefit of roughly $2,071 following the 2026 COLA, notes income phaseouts on the One Big Beautiful Bill’s $6,000 senior deduction, and incorporates Northwestern Mutual’s 2026 finding that Americans believe they need $1.46 million to retire comfortably.

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