A “conversion out” line on your 401(k) statement records money that left your traditional, pre-tax 401(k) balance and moved into a Roth account through a Roth conversion. So when you’re asking what conversion out means on a 401(k) statement, the short answer is: the dollars didn’t leave your retirement savings, they changed tax character. You should see a matching “conversion in” entry on the receiving Roth account, whether that’s a designated Roth inside the same plan or a Roth IRA at an outside custodian. The catch is that the converted amount counts as taxable income for the year it moved.
Where the Money Actually Went
A Roth conversion from a 401(k) takes one of two paths, and your statement should make clear which one applied.
The first is an in-plan Roth conversion. The money moves from your traditional 401(k) balance to a designated Roth account inside the same employer plan. Your funds stay under the plan’s investment menu and rules. Not every plan offers this option, but if yours does, the conversion may have been triggered by an election you made at enrollment or by an automatic feature your employer added.
The second is a rollover to a Roth IRA. The money leaves the 401(k) entirely and lands in a Roth IRA at a brokerage or custodian of your choice. You get a much wider range of investments, but the money is no longer under your employer’s plan.
Both paths trigger the same federal income tax on the converted amount. The differences show up in creditor protection and control. An in-plan conversion keeps your money under the federal anti-alienation protections of ERISA, which shield 401(k) assets from most creditors outside of bankruptcy. Once funds land in a Roth IRA, creditor protection depends on state law and is often less complete. In bankruptcy, IRA assets are exempt up to $1,711,975 as of April 2025.
If the “conversion out” transaction is a surprise, that’s the first thing to sort out. Call your plan administrator, ask which type of conversion was processed, when, and on whose authorization. Plans that offer automatic in-plan Roth conversions on after-tax contributions can generate these entries without any recent action on your part.
What It Costs You at Tax Time
The entire pre-tax amount you converted gets added to your gross income for the year the transaction happened. Convert $80,000 in June, and your taxable income for the year rises by $80,000 on top of your salary and any other earnings.1Internal Revenue Service. Retirement Plans FAQs Regarding IRAs That bump can push you into a higher federal tax bracket, though only the income falling within each bracket gets taxed at that bracket’s rate.
For 2026, federal rates range from 10% to 37%. A single filer crosses from the 24% bracket into the 32% bracket at $201,775 of taxable income; married couples filing jointly cross that threshold at $403,550.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 Most states also treat the converted amount as taxable income, with rates from 0% in states with no income tax to over 13% in the highest-tax states. A handful of states offer partial exemptions for retirement income based on age or income.
Two secondary effects catch people off guard.
Medicare Premiums Two Years Later
Medicare bases Part B and Part D premiums on your modified adjusted gross income from two years prior. For 2026, a single filer whose income exceeds $109,000 (or $218,000 for joint filers) pays a monthly surcharge on top of the standard Part B premium. At the first tier, the extra cost is $81.20 per month for Part B plus $14.50 for Part D. The surcharges climb from there, reaching an additional $487.00 per month for Part B alone once income hits $500,000 for a single filer.3Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B Premiums and Deductibles A $100,000 conversion in 2026 could mean hundreds of dollars more per month in Medicare premiums starting in 2028.
Social Security Taxation
If you’re already collecting Social Security, the conversion counts in the “combined income” formula the IRS uses to tax benefits. Once combined income exceeds $34,000 for single filers or $44,000 for joint filers, up to 85% of your Social Security becomes taxable. The upside comes later: once the money is in a Roth account, qualified withdrawals won’t affect Social Security taxation at all.
Estimated Payments
A large conversion creates a spike in income that ordinary paycheck withholding won’t cover. You generally owe estimated tax payments if you’ll owe $1,000 or more after subtracting withholding and credits, and missing them can trigger an underpayment penalty. If the conversion happened late in the year, you can use the annualized income installment method on Form 2210 to show that the income arrived unevenly and reduce or eliminate the penalty.4Internal Revenue Service. Estimated Taxes
The Five-Year Clock That Now Applies
Once dollars are converted, a separate five-year waiting period attaches to that specific conversion. Withdraw the converted amount before five years have passed while you’re under age 59½, and you owe a 10% early withdrawal penalty on the taxable portion, even though you already paid income tax on it at conversion.5Internal Revenue Service. Topic No. 557, Additional Tax on Early Distributions From Traditional and Roth IRAs Each conversion has its own clock. Once you turn 59½, the penalty no longer applies regardless of how recently you converted.
This is separate from the general Roth five-year clock, which starts with your first contribution to any Roth IRA and governs when earnings can come out tax-free. Both need to be satisfied before a distribution of earnings qualifies as fully tax-free, along with reaching 59½ or meeting another qualifying exception like disability or death.6Office of the Law Revision Counsel. 26 USC 408A – Roth IRAs
Exceptions to the 10% early withdrawal penalty include disability, a first-time home purchase up to $10,000, and qualified higher education expenses.5Internal Revenue Service. Topic No. 557, Additional Tax on Early Distributions From Traditional and Roth IRAs
If Your 401(k) Had After-Tax Contributions
If your 401(k) balance was a mix of pre-tax and after-tax money, the tax treatment of the conversion depends on how the plan handled the split. The general rule is pro-rata: each distribution from the plan must include a proportional share of pre-tax and after-tax dollars, so you can’t cherry-pick only the after-tax portion.7Internal Revenue Service. Rollovers of After-Tax Contributions in Retirement Plans
There’s a workaround under IRS Notice 2014-54. When a distribution from a 401(k) is split between two destinations at the same time, the pre-tax dollars can go to a traditional IRA and the after-tax dollars to a Roth IRA.8Internal Revenue Service. Notice 2014-54 – Guidance on Allocation of After-Tax Amounts to Rollovers If that’s what happened on your statement, only the pre-tax portion is taxable. Ask the plan administrator to show the pre-tax and after-tax breakdown of the distribution so you know what to report.
How It Gets Reported to the IRS
Your plan administrator will issue a Form 1099-R for the tax year of the conversion, showing the distribution from the traditional balance and the taxable portion. On your tax return, you report the Roth conversion on Form 8606, which calculates the taxable and nontaxable portions.9Internal Revenue Service. Instructions for Form 8606 Keep the 1099-R and your statement showing the “conversion out” and “conversion in” entries together with your tax records. Errors on Form 8606 are a common source of IRS notices, particularly when after-tax contributions are involved.
If You Didn’t Authorize It
A “conversion out” you didn’t ask for isn’t necessarily an error, but it should be explained. Possibilities to run down with your plan administrator:
- An election you made at enrollment or during a benefits change that set up automatic in-plan Roth conversions on some portion of your contributions.
- A plan feature added by your employer that converts after-tax contributions to Roth automatically.
- A processing error, in which case you’ll want the transaction reviewed before the Form 1099-R is finalized for the year.
Get the date, the dollar amount, the source (pre-tax or after-tax), and the destination account in writing. Those four facts determine what you owe, when you owe it, and which clock started running.