How Much Tax Do I Pay on a $100K 401(k) Withdrawal?

A $100,000 traditional 401(k) withdrawal typically costs somewhere between $13,000 and $31,000 in federal tax alone, and can run higher once state income tax and the 10% early withdrawal penalty are added. The exact figure depends on three things: how much other income you have that year, your filing status, and whether you’re under age 59½. The plan administrator withholds 20% up front and sends you the other $80,000, but that 20% is a prepayment, not the final bill.

The 20% Withheld Is Not Your Actual Tax

Federal law requires your plan administrator to withhold 20% for federal income tax when a 401(k) distribution is paid directly to you instead of rolled into another retirement account.¹ On a $100,000 distribution, $20,000 goes to the IRS and $80,000 lands in your account.

That $20,000 is closer to paycheck withholding than a final tax. The plan reports the distribution and the amount withheld on Form 1099-R, and you reconcile it on your return.² You can’t elect less than 20%, but you can ask for more by filing Form W-4R with your plan administrator before the money goes out.³ Whether state tax is also withheld depends on the state.

How the Withdrawal Stacks on Your Income

The entire $100,000 counts as ordinary income in the year you receive it, taxed at the same rates as wages. Because federal brackets are progressive, the withdrawal doesn’t get taxed at a single rate. It stacks on top of your other income, and each slice is taxed at the rate for the bracket it falls into. The 2026 brackets for a single filer:⁴

10% up to $12,400
12% from $12,401 to $50,400
22% from $50,401 to $105,700
24% from $105,701 to $256,225
32% from $256,226 to $640,600

The 2026 standard deduction is $16,100 for single filers and $32,200 for married filing jointly, and it comes off before the brackets apply.⁴

If the Withdrawal Is Your Only Income

You’re single, you withdraw $100,000, and you have no other income in 2026. After the $16,100 standard deduction, your taxable income is $83,900. The tax:

10% on the first $12,400: $1,240
12% on the next $38,000: $4,560
22% on the remaining $33,500: $7,370

Total federal income tax: about $13,170, an effective rate of roughly 13.2% on the full $100,000. The $20,000 withheld overshoots, so you’d get about $6,830 back. This is one of the few situations where the standard 20% withholding is more than enough.

If You Also Earn $50,000 From a Job

Add $50,000 in salary and your gross income becomes $150,000. After the standard deduction, taxable income is $133,900, and the total federal tax comes to about $24,734. Without the withdrawal, the tax on your $50,000 salary alone would be roughly $3,820. The difference, about $20,914, is what the $100,000 withdrawal actually costs you in federal income tax. That already exceeds the $20,000 withheld, and the 10% penalty hasn’t entered the picture yet.

The stacking effect is what surprises people. Your withdrawal doesn’t start at the bottom rung of the bracket ladder; it starts wherever your other income stops. A married couple filing jointly gets wider brackets, so the same $100,000 may stay in lower brackets longer, but the mechanics are identical.

Add 10% If You’re Under 59½

Take money out of a 401(k) before age 59½ and the IRS adds a flat 10% penalty on top of ordinary income tax.⁵ On $100,000, that’s $10,000, regardless of your bracket or filing status. The penalty is calculated on Form 5329 and added to your Form 1040 liability.⁶

Returning to the single filer with $50,000 in salary: $20,914 of federal income tax plus the $10,000 penalty brings the federal total to about $30,914. After the $20,000 withheld, you’d owe roughly $10,914 in April.

When the Penalty Doesn’t Apply

Several situations waive the 10%, though you still owe regular income tax on the full amount:⁷

You separated from your employer during or after the calendar year you turned 55, and you’re pulling from that employer’s plan. Public safety employees of state or local governments qualify starting at age 50.⁵
You’re totally and permanently disabled, certified by a physician.⁸
You have unreimbursed medical expenses above 7.5% of AGI, up to the amount that exceeds the floor.
You commit to substantially equal periodic payments based on IRS life expectancy tables, and stick with them until the later of five years or age 59½.⁹
A physician certifies you’re expected to die within 84 months (terminal illness).
You’re a victim of domestic abuse by a spouse or partner within the past 12 months, up to the lesser of $10,000 (indexed) or 50% of your vested balance.
You suffered economic loss from a federally declared disaster.

One trap worth calling out: the $10,000 first-time homebuyer exception applies to IRAs, not 401(k)s. Pulling from a 401(k) to buy a first home doesn’t waive the penalty on its own.⁷

State Tax on Top

Most states treat 401(k) distributions as ordinary income. State income tax rates run from zero in states with no income tax to over 13% in the highest-tax jurisdictions. A 5% effective state rate adds about $5,000 to the bill on a $100,000 withdrawal. A handful of states partially or fully exempt retirement income, with widely varying dollar limits and eligibility rules.

State withholding isn’t always automatic. If your plan didn’t withhold, you’ll owe the full state tax when you file.

The Costs You Didn’t See Coming

A $100,000 spike in income can raise other bills that show up months or years later.

Medicare beneficiaries pay income-related surcharges on Part B and Part D premiums when modified adjusted gross income crosses certain thresholds. For 2026, the first surcharge tier starts at $109,000 for single filers and $218,000 for married couples filing jointly, based on your return from two years earlier. Surcharges climb steeply through several tiers and can add hundreds of dollars per month. If you already took the distribution, you can sometimes request a reduction by filing a life-changing event form with Social Security, but a routine withdrawal doesn’t qualify.

If you get Affordable Care Act marketplace subsidies, the AGI jump can shrink or wipe out your premium tax credits, and you’d owe the excess back when you file.

Roth 401(k) Withdrawals Are Different

Everything above assumes a traditional 401(k) funded with pre-tax dollars. A Roth 401(k) works in reverse: you already paid tax on the contributions, so a qualified distribution comes out entirely tax-free and penalty-free. Qualified means the account has been open at least five years and you’re 59½ or older, permanently disabled, or deceased.¹⁰ If a Roth distribution doesn’t qualify, only the earnings portion is taxable and potentially subject to the 10% penalty; the contributions still come out tax-free.

Avoiding an Underpayment Penalty

When the 20% withheld falls short, you may owe an underpayment penalty in addition to the tax. You avoid it by meeting one of these safe harbors:¹¹

Total withholding and estimated payments cover at least 90% of your current-year tax.
Payments equal at least 100% of last year’s tax, if last year’s AGI was $150,000 or less ($75,000 if married filing separately).
Payments equal at least 110% of last year’s tax, if last year’s AGI was above $150,000.

If the withdrawal happens early in the year, quarterly estimated payments can cover the gap. Late in the year, the simplest fix is asking for higher withholding on Form W-4R when you request the distribution, say 30% or 35% if you’re in a higher bracket.³

Four Scenarios for a $100,000 Withdrawal

Federal-only numbers for a single filer in 2026:⁴

No other income, age 60: about $13,170 in federal tax. The 20% withholding produces roughly a $6,830 refund.
No other income, age 45: about $13,170 in income tax plus $10,000 in penalty, totaling roughly $23,170. You’d owe about $3,170 at filing.
$50,000 salary, age 60: the withdrawal adds about $20,914 in federal tax. The $20,000 withheld falls about $914 short.
$50,000 salary, age 45: about $20,914 in income tax plus $10,000 penalty, totaling $30,914. After withholding, you’d owe roughly $10,914.

State income tax pushes each of these higher. A 5% effective state rate adds around $5,000; the highest-tax states add $10,000 or more.

The gap between the 20% withheld and what you actually owe widens as your other income grows. Someone earning $100,000 from a job who also withdraws $100,000 will see a meaningful chunk of the distribution land in the 24% or 32% bracket, and the withholding shortfall grows with it. Under 59½ in that situation, the combination of bracket stacking and the 10% penalty can consume 35% to 40% of the distribution before state tax enters the picture.

1
Office of the Law Revision Counsel. 26 USC 3405 – Special Rules for Pensions, Annuities, and Certain Other Deferred Income
2
Internal Revenue Service. Instructions for Forms 1099-R and 5498
3
Internal Revenue Service. 2026 Form W-4R
4
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
5
Internal Revenue Service. Topic No. 558 – Additional Tax on Early Distributions From Retirement Plans Other Than IRAs
6
Internal Revenue Service. Instructions for Form 5329
7
Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions
8
Office of the Law Revision Counsel. 26 USC 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts
9
Internal Revenue Service. Substantially Equal Periodic Payments
10
Internal Revenue Service. Roth Account in Your Retirement Plan
11
Office of the Law Revision Counsel. 26 USC 6654 – Failure by Individual to Pay Estimated Income Tax