How a 401(k)-to-Roth conversion works

A 401(k)-to-Roth rollover means moving money from your employer's 401(k) plan into a Roth IRA you control. The mechanics are straightforward: your 401(k) custodian sends the money to your Roth IRA custodian (usually a bank or brokerage), and you report the move on your tax return. The catch is taxes — you pay income tax on the full amount you move in the year you move it, because you are converting pre-tax 401(k) money into after-tax Roth money.

You do not have to move all your 401(k) money at once. You can roll over part of it and leave the rest in the 401(k), or split the move across multiple years to spread out the tax bill. The IRS does not limit how many times you can do this, though your plan administrator and the receiving Roth IRA custodian each have their own rules about frequency.

Key Takeaways

  • You pay ordinary income tax on the full amount you convert in the year you convert it, so a large rollover can push you into a higher tax bracket.
  • You must have earned income in the year you open or fund a Roth IRA, but a rollover does not count as earned income — so you can only roll over if you already have a Roth IRA open.
  • If your 401(k) holds both pre-tax and after-tax money, the IRS pro-rata rule means you cannot convert only the after-tax portion — you must convert a proportional mix of both.
  • The 60-day rule gives you 60 days to complete an indirect rollover (money goes to you first, then to the Roth), but a direct rollover (custodian to custodian) has no time limit.
  • Once money lands in your Roth IRA, you can withdraw your contributions anytime tax-free, but earnings stay locked until age 59½ unless an exception applies.

Direct rollover versus indirect rollover

A direct rollover means the 401(k) custodian sends the money straight to your Roth IRA custodian. You never touch it. This is the cleanest route — no withholding, no time pressure, no paperwork mistakes on your end. You ask your 401(k) plan administrator for a direct rollover form, name your Roth IRA custodian and account number, and sign. The money moves between institutions.

An indirect rollover means the 401(k) custodian sends the check to you, and you deposit it into your Roth IRA within 60 days. The IRS requires the custodian to withhold 20 percent for federal income tax, so if you roll over $10,000, you receive $8,000 and the custodian sends $2,000 to the IRS. To complete the rollover, you must deposit the full $10,000 into your Roth within 60 days — meaning you have to cover the $2,000 withholding from your own money or the $2,000 becomes a taxable distribution and a premature withdrawal penalty may apply. Indirect rollovers are riskier and more expensive unless you have cash on hand to make up the withholding.

If you miss the 60-day deadline on an indirect rollover, the IRS treats the money as a distribution, not a rollover. You owe income tax on the full amount plus a 10 percent early withdrawal penalty if you are under 59½, even if you deposit it into the Roth later.

Tax consequences of converting

The year you convert, you report the full rollover amount as ordinary income on your federal tax return. If you convert $50,000, you add $50,000 to your taxable income for that year. This can push you into a higher tax bracket, trigger the net investment income tax (3.8 percent on high earners), or reduce your deductions and credits if your income phases them out.

Some people convert in years when their income is lower — for example, the year they retire before Social Security starts, or a year with a business loss. Others convert in chunks over several years to keep each year's tax bill manageable. There is no rule against this; you can do multiple conversions whenever you choose.

If your 401(k) contains both pre-tax contributions (the money that reduced your taxable income when you contributed it) and after-tax contributions (money you put in with dollars you already paid tax on), the IRS pro-rata rule applies. You cannot convert only the after-tax portion. Instead, you must convert a proportional mix. If 80 percent of your 401(k) is pre-tax and 20 percent is after-tax, any conversion must be 80 percent pre-tax and 20 percent after-tax. Only the pre-tax portion is taxable on conversion.

Who can roll over a 401(k) to a Roth IRA

You can roll over a 401(k) to a Roth IRA if you are no longer employed by the company that sponsored the plan, or if your plan allows in-service rollovers (some do, some do not — ask your plan administrator). You do not need to be retired or a certain age. You can roll over at 30, 40, or 65.

The only hard requirement is that you must have a Roth IRA open before the money arrives. You cannot open a Roth IRA with a rollover; you must open it first with earned income (wages, self-employment income, or taxable alimony). Once the account exists, you can roll over 401(k) money into it. If you do not have a Roth IRA yet, open one at a bank or brokerage, make a small contribution from earned income if needed, and then initiate the rollover.

There are no income limits on rollovers. The income limits that block direct Roth contributions do not apply to conversions or rollovers, so high earners can roll over a 401(k) to a Roth even if their income is too high to contribute directly.

Step-by-step process for a direct rollover

First, contact your 401(k) plan administrator (usually through your company's benefits department or the plan's website) and ask for a direct rollover form. Some plans call it a "distribution request" or "rollover authorization." Tell them you want a direct rollover to a Roth IRA, not a check to you.

Second, open a Roth IRA if you do not have one. You need the account number and the custodian's name and address. Most custodians are large brokerages like Fidelity, Vanguard, or Schwab, or banks like Charles Schwab Bank or Ally Bank.

Third, fill out the rollover form with your Roth IRA custodian's details. The form will ask for the custodian's name, address, and your account number. Double-check the account number — a typo can send the money to the wrong place and create a mess.

Fourth, sign and return the form to your 401(k) plan administrator. They will contact your Roth IRA custodian directly. The transfer usually takes one to two weeks, though it can take longer if either institution is slow.

Fifth, confirm the money arrived in your Roth IRA. Log into your account and verify the deposit. Keep the confirmation and the rollover paperwork for your records.

What happens if you have multiple 401(k)s

If you have worked for several employers and have multiple 401(k)s, you can roll over one, some, or all of them to a single Roth IRA. There is no limit on how many 401(k)s you can consolidate into one Roth. This simplifies your finances and makes it easier to manage your investments in one place.

However, if you have both a 401(k) and an IRA (traditional or Roth) from a previous employer, the pro-rata rule still applies across all your IRAs combined. If you have a traditional IRA with $20,000 of pre-tax money and a 401(k) with $10,000 of pre-tax money, and you convert the 401(k) to a Roth, the IRS treats it as converting $30,000 total (the 401(k) plus the traditional IRA combined), and the tax is calculated on the proportion of pre-tax money in the combined total. This can make conversions more expensive if you have existing traditional IRA balances.

Frequently Asked Questions

Can I roll over a 401(k) to a Roth IRA while I still work for the company?

Only if your plan allows in-service rollovers. Some employer plans permit this; others do not. Contact your benefits department or plan administrator and ask whether in-service rollovers to a Roth IRA are allowed. If they are, you can roll over while still employed. If not, you must wait until you leave the job.

What if I already have a traditional IRA with money in it?

The pro-rata rule applies. The IRS combines your traditional IRA balance with the 401(k) amount you are converting and calculates the tax based on the proportion of pre-tax money in the combined total. If you want to avoid this, you can roll your traditional IRA into your 401(k) first (if the plan allows), then convert the 401(k) to a Roth. This removes the traditional IRA from the pro-rata calculation.

Do I have to convert the entire 401(k) at once?

No. You can convert part of it and leave the rest in the 401(k), or convert in multiple batches over several years. Each conversion is a separate taxable event, so you can spread the tax bill across years if that makes sense for your situation.

What if I need the money before age 59½?

You can withdraw your contributions (the amount you converted) anytime tax-free. Earnings on those contributions are locked until 59½ unless you meet an exception like disability or a Roth IRA that has been open for five years and you are over 59½. Withdrawing earnings early usually triggers a 10 percent penalty plus income tax.

Can I undo a conversion if the market drops after I convert?

You can recharacterize a conversion — essentially undoing it — but only if you do so by the tax filing deadline (usually October 15 of the following year, including extensions). After that date, the conversion is permanent. Some people recharacterize if the account value drops significantly after conversion, because it reduces the tax bill. You would owe tax only on the lower value, not the original amount converted.