401k Withdrawal Tax Calculator (2026): What You Keep After Tax, Penalty and Withholding

Last updated October 10, 2026. Figures checked against IRS Rev. Proc. 2025-32, IRS Topics 413 and 558, Form W-4R and the California FTB 3805P instructions. Sources are listed at the end.

How much tax will I pay on a 401(k) withdrawal?

The money you put into a traditional 401(k) was never taxed, so every dollar that comes out is taxed as ordinary income in the year you take it. Three things decide the bill:

1. Federal income tax at your marginal rate. The withdrawal is stacked on top of your wages, pension, interest and the taxable part of your Social Security. Only the part that crosses into a higher bracket is taxed at the higher rate.
2. The 10% additional tax if you are under 59½ and no exception applies.
3. State income tax, which runs from zero in nine states to over 13% at the top in California.

A Roth 401(k) works differently: a qualified withdrawal (generally after 59½ and once the account is at least five years old) is tax-free, and this calculator does not apply to it.

2026 federal tax brackets (taxable income)

These apply to taxable income, after deductions. The 2026 standard deduction is $16,100 single and $32,200 married filing jointly (IRS, 2026 inflation adjustments). If you are 65 or older, add $2,050 if single or $1,650 for each spouse 65 or older if married. From 2025 through 2028, anyone 65 or older can also take an extra $6,000 senior deduction ($12,000 for a couple who both qualify), which phases out above $75,000 of modified adjusted gross income ($150,000 joint) (IRS). Example: a married couple, both 66, with income under $150,000 can deduct $32,200 + $3,300 + $12,000 = $47,500 in 2026 before any bracket applies. That is why the calculator asks for your other income after deductions.

Worked examples: $50,000 and $100,000 withdrawals in 2026

Each example uses the 2026 brackets above and the same math as the calculator.

Why is there a 20% tax on a 401(k) withdrawal?

It is not a tax. It is mandatory federal withholding. When a 401(k) pays an eligible rollover distribution to you in cash, the plan must withhold 20% and send it to the IRS, even if you plan to roll the money over later. At filing, the 20% is credited against what you actually owe.

• 20% can be too little. Under 59½, or in the 22% bracket and up, the real federal bill plus penalty often exceeds 20% (example 2). You can ask for more on Form W-4R, but not less than 20%.
• 20% can be too much. In the 10% or 12% bracket the withholding exceeds the tax and the difference comes back as a refund (example 1).
• A direct rollover avoids it. If the plan sends the money straight to an IRA or a new employer plan, nothing is withheld and nothing is taxed.
• A 60-day rollover needs the 20% made up. If you take the check and roll it over within 60 days, you must add the withheld 20% from other money to roll over the full amount. Whatever you do not roll over is taxable.
• Not every withdrawal gets 20%. Required minimum distributions and hardship distributions cannot be rolled over, so they are not eligible rollover distributions. Lump payments of those default to 10% withholding, which you can change on Form W-4R.

401(k) early withdrawal penalty: the 10% and its exceptions

Withdrawals before age 59½ generally owe an additional 10% tax on the taxable amount, reported on Schedule 2 and, when needed, Form 5329. The IRS lists exceptions for 401(k) and similar plans, including:

• Rule of 55: you leave the employer in or after the calendar year you turn 55 (50 for qualified public safety employees). It applies only to the plan of the employer you left, not to IRAs, so rolling that money to an IRA first gives the exception up.
• Substantially equal periodic payments over your life expectancy (from an employer plan, after you separate from service).
• Total and permanent disability, or a terminal illness certified by a physician.
• Death: payments to a beneficiary or estate.
• A qualified domestic relations order paying a former spouse.
• Unreimbursed medical expenses above 7.5% of adjusted gross income.
• Birth or adoption: up to $5,000 per child.
• Emergency personal expense: one distribution a year of up to $1,000.
• Domestic abuse victim: up to the lesser of $10,500 in 2026 (IRS Notice 2025-67) or 50% of the account.
• Federally declared disaster: up to $22,000 for those with an economic loss.
• An IRS levy on the plan, and qualified reservist distributions.

The penalty does not apply to most governmental 457(b) plans. Watch for two exceptions that people assume cover a 401(k) but do not: first-time homebuyer and higher-education withdrawals are penalty-free only from an IRA.

State tax on 401(k) withdrawals

Rules change and the conditions matter, so confirm your own state’s treatment with its revenue department or your preparer. The calculator uses a flat state rate as an estimate and adds the California 2.5% when you pick a California rate and are under 59½.

Taxes on a 401(k) withdrawal after 59½

After 59½ the penalty is gone, but the withdrawal is still ordinary income. Required minimum distributions begin at 73 for most people retiring now (75 for those born in 1960 or later). Withdrawals in your 60s can also raise two other costs that are easy to miss: Medicare Part B and D premiums (IRMAA), which look at your income from two years earlier, and the share of your Social Security that is taxable. Check both with the IRMAA calculator and the Social Security tax calculator.

How to reduce the tax on a 401(k) withdrawal

• Spread it across tax years. Two $25,000 withdrawals in December and January can keep income in a lower bracket than one $50,000 withdrawal.
• Fill low brackets on purpose. Years between retirement and Social Security or RMDs are often the cheapest years to draw down, or to convert to Roth (Roth conversion calculator).
• Roll over instead of cashing out when you change jobs. A direct rollover is not taxed and has no withholding.
• Time a job exit around the rule of 55 if you will need the money before 59½.
• Plan for RMDs early. See the 2026 RMD table and how to reduce taxes on RMDs. Charitable givers 70½ or older can use a qualified charitable distribution, but only from an IRA (QCD guide).

401(k) withdrawal tax FAQ

How much will I pay in taxes if I withdraw from my 401(k)?

Your marginal federal rate on the withdrawal (10% to 37% in 2026), your state rate, and 10% more if you are under 59½ without an exception. In example 1 above, a $50,000 withdrawal cost $9,420 in total tax (18.8%); in example 2 it cost about $20,860 (41.7%).

Why is there a 20% tax on a 401(k) withdrawal?

The 20% is mandatory federal withholding on cash distributions that could have been rolled over. It is credited against your actual tax when you file, so it can produce a refund or a balance due.

How much is taxed on a 401(k) early withdrawal?

The full taxable amount is ordinary income, plus a 10% additional federal tax (and 2.5% more in California) unless an exception such as the rule of 55, disability or substantially equal payments applies.

What are the downsides of taking a 401(k) withdrawal?

The tax and possible penalty, the loss of future tax-deferred growth on the money, the chance of moving into a higher bracket, and knock-on costs such as higher Medicare premiums or more of your Social Security being taxed. Money taken out generally cannot be put back, except through a rollover within 60 days.

Can I withdraw 100% of my 401(k)?

Usually yes once you leave the employer: most plans allow a full lump-sum distribution. While you still work there, plan rules limit withdrawals, often to hardship or in-service withdrawals after 59½. Taking it all in one year stacks the whole balance into one tax return, which is often the most expensive way to do it.

Do I pay tax on a 401(k) withdrawal after 59½?

Yes, ordinary income tax still applies to traditional 401(k) money. Only the 10% penalty goes away. Qualified Roth 401(k) withdrawals are tax-free.

Is 20% withholding enough?

It depends on your bracket. If your top rate is 22% or higher, or you owe the 10% penalty, 20% will usually fall short. You can raise the rate on Form W-4R or make an estimated tax payment.