Yes, you can roll over a 401(k) to a Roth IRA, but you will owe income tax on the money you convert

A rollover means moving money from one retirement account to another. When you move funds from a traditional 401(k) to a Roth IRA, the IRS treats it as a conversion — you pay income tax on the full amount you move in the year you move it, then the money grows tax-free in the Roth account from that point forward.

You can do this rollover at any time, whether you are still working at the company or have left. The key constraint is the tax bill: if you roll over $50,000, you owe federal income tax on $50,000 in that tax year. That tax is due when you file your return, not when you do the rollover.

There is no income limit that stops you from converting a 401(k) to a Roth IRA, unlike the direct contribution limits that apply to Roth IRAs. This is why conversions are often used by higher-income earners who cannot contribute to a Roth IRA directly.

Key Takeaways

  • You pay income tax on the full amount you convert in the year of the rollover, so a $50,000 conversion adds $50,000 to your taxable income for that year.
  • The rollover itself is not taxed or penalized — only the conversion to Roth status triggers the tax bill.
  • You can roll over a 401(k) to a Roth IRA at any age and at any time, whether you are still employed or retired.
  • After the rollover, the money in the Roth IRA grows tax-free and you can withdraw earnings tax-free after age 59½ if the account has been open at least five years.
  • If you have other traditional IRAs or SEP IRAs, the IRS may treat all of them as one pool for tax purposes when you convert, which can increase your tax bill.

How the rollover process actually works

There are two ways to move the money: a direct rollover or an indirect rollover. A direct rollover is simpler and safer. You contact your 401(k) plan administrator and ask them to send the money directly to the Roth IRA custodian (usually a bank or brokerage). The money never touches your hands, and there is no withholding or time limit.

An indirect rollover means the 401(k) plan sends you a check. You then deposit it into a Roth IRA within 60 days. The plan will withhold 20% for federal taxes automatically, so if you roll over $50,000, you receive a check for $40,000 and owe $10,000 in withholding. You must deposit the full $50,000 into the Roth IRA within 60 days to avoid penalties — if you only deposit the $40,000 you received, the missing $10,000 is treated as a distribution and taxed again.

Most people choose direct rollover because it avoids the withholding trap and the 60-day deadline. Contact your 401(k) plan administrator and ask for the direct rollover form. They will ask for the name and account number of your Roth IRA custodian. The transfer usually takes one to two weeks.

The tax bill you will owe

When you convert a 401(k) to a Roth IRA, the IRS adds the full conversion amount to your taxable income for that year. If you earn $80,000 and convert $50,000, your taxable income becomes $130,000 for that year. You pay federal income tax at your marginal rate — the tax bracket you fall into based on your total income.

State income tax also applies in most states. If you live in a state with income tax, you will owe state tax on the conversion as well. A few states (like Florida, Texas, and Wyoming) have no state income tax, so residents of those states owe only federal tax.

The tax is not withheld automatically unless you request it. When you file your tax return, you report the conversion on Form 8606 and pay the tax owed. If you expect a large tax bill, you can make estimated tax payments during the year to avoid penalties.

The pro-rata rule and why it matters if you have other IRAs

If you have a traditional IRA, SEP IRA, or SIMPLE IRA in addition to your 401(k), the IRS applies the pro-rata rule when you convert. This rule treats all your traditional and SEP IRAs as a single pool for tax purposes. If 30% of that pool is pre-tax money and 70% is after-tax money, then 30% of your conversion is taxable and 70% is not.

This rule can significantly increase your tax bill. Suppose you have a traditional IRA with $100,000 in pre-tax contributions and a 401(k) with $50,000 in pre-tax contributions. If you convert only the 401(k), the IRS sees $150,000 in pre-tax money total. Your conversion is treated as 100% pre-tax ($150,000 ÷ $150,000), so you owe tax on the full $50,000 you converted.

The pro-rata rule does not apply to employer plans like 401(k)s, 403(b)s, or 457 plans — only to IRAs. If you have a traditional IRA and want to convert a 401(k) to a Roth, consider rolling the traditional IRA into your employer plan first (if your plan allows it), which removes it from the pro-rata calculation and lowers your tax bill on the conversion.

When a rollover makes sense financially

A conversion is most useful if you expect to be in a lower tax bracket in the year you convert than you will be in retirement. If you leave your job mid-year, take a sabbatical, or have a year with unusually low income, that year may be a good time to convert. You pay tax at a lower rate now and avoid paying tax on the growth later.

Conversions also make sense if you have a large amount of pre-tax retirement savings and expect tax rates to rise in the future. By converting now at today's rates, you lock in the tax cost and let the money grow tax-free in the Roth.

A conversion does not make sense if you will be in a higher tax bracket in the year of conversion than you expect to be in retirement. If you are still working full-time and earn a high income, converting a large amount will push you into a higher tax bracket and cost more than waiting until you retire.

Roth conversion rules and restrictions

There is no age limit for conversions — you can convert at any age, even after 70½. There is also no income limit, which is why high-income earners use conversions to fund Roth IRAs when they cannot contribute directly.

You cannot undo a conversion by rolling it back into a 401(k). Once money is in a Roth IRA, it stays there. You can move it to another Roth IRA, but you cannot reverse the conversion to avoid the tax bill.

If you convert and then realize the tax bill is too high, you can file an amended tax return to report the conversion differently, but this is complex and requires professional tax help. It is better to plan the conversion carefully before you do it.

What happens to the money after the rollover

After the rollover, the money in your Roth IRA grows tax-free. You can withdraw contributions (the money you put in) at any time without tax or penalty. You can withdraw earnings (the growth) tax-free after age 59½ if the Roth IRA has been open for at least five years.

The five-year rule is per account, not per conversion. If you open a Roth IRA and convert money into it, the five-year clock starts on the date you open the account. If you already have a Roth IRA that is more than five years old, the five-year requirement is already met for any conversion you do.

You are not required to take withdrawals from a Roth IRA at any age, unlike traditional IRAs. This makes Roth accounts useful for leaving money to heirs or for people who do not need the money in retirement.

Frequently Asked Questions

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

No. You can convert part of your 401(k) and leave the rest in the plan or roll it to a traditional IRA. This lets you spread the tax bill over multiple years if you convert in chunks. Each conversion is taxed separately in the year it occurs.

What if I leave my job — do I have to roll over my 401(k)?

No. You can leave it in your former employer's plan, roll it to a traditional IRA, roll it to your new employer's plan (if allowed), or convert it to a Roth IRA. You are not required to do anything unless your plan balance is very small (usually under $5,000), in which case the plan may force a distribution.

Can I convert a 401(k) loan to a Roth IRA?

No. If you have an outstanding loan from your 401(k), you cannot convert the borrowed amount. You must repay the loan first or let it be treated as a distribution (which triggers tax and penalties if you are under 59½). Only the vested balance available for rollover can be converted.

Will a conversion affect my Social Security or Medicare benefits?

A Roth conversion increases your taxable income in the year of conversion, which can affect your Medicare premiums if you are on Medicare. It does not directly affect Social Security benefits, but higher income can trigger taxation of your Social Security benefits. Consult a tax professional if you are on Medicare or approaching it.

What if I convert and then the market drops — can I undo it?

You cannot undo a conversion by rolling the money back. However, you can file an amended tax return to report the conversion differently if you did it in error. This is rare and requires professional help. Once you convert, the tax consequence is locked in regardless of market performance.