A direct rollover from a pretax 401(k) to a Roth IRA is generally taxable as a conversion, even when Form 1099-R uses code G. Estimate the pretax amount, add it to projected income, calculate federal and state effects, and pay tax from outside cash when possible. A direct transfer avoids the 60-day rollover problem but does not erase conversion income.
Forum threads repeatedly show taxpayers assuming code G makes every rollover nontaxable. The current reporting questions establish the failure point. IRS Publication 575 and Form 1099-R instructions distinguish pretax-to-traditional rollovers from pretax-to-Roth conversions.
Start here: a practical action plan
- Open every official source linked in the guide and confirm that the rule still applies to the exact account, tax year, and transaction.
- Collect the statements, forms, notices, and confirmations named in the guide before changing the account or filing a return.
- Replace the hypothetical figures with actual amounts, reproduce the arithmetic, and save the calculation with the source records.
- Record the next operational or filing deadline and obtain written confirmation after the correction, transfer, or payment posts.
- Treating a forum reply or a custodian button as authority for the tax, loan, or account result.
- Using a gross balance when the rule depends on source, basis, accrued interest, reimbursements, or prior-year activity.
- Losing the dated records needed to reconcile a later tax form, servicer history, notice, or corrected statement.
Name the destination before approving the transfer
Ask the receiving firm to state in writing whether the account is a traditional IRA or Roth IRA. A traditional rollover IRA preserves pretax treatment. A Roth IRA accepts converted dollars. The difference is tax treatment, not merely an investment choice.
Request a source breakdown from the 401(k): pretax employee deferrals, employer contributions, designated Roth money, and after-tax basis. Do not assume the entire balance has one tax character. Plans can issue separate checks or forms for different sources.
Worked example: conversion income changes the cash plan
Example: a $74,000 plan balance contains $68,000 of pretax money and $6,000 of after-tax basis, and the full amount goes directly to a Roth IRA. In a simplified illustration, $68,000 is the potential taxable conversion and $6,000 is basis recovery, subject to the plan records and tax rules.
If the household estimates a 22 percent federal marginal rate and 5 percent state rate on the full $68,000, a rough reserve is $18,360: $14,960 federal plus $3,400 state. This is a liquidity estimate, not a tax return, because brackets, deductions, credits, and other income matter.
| Component | Amount | Planning treatment |
|---|---|---|
| Pretax plan money | $68,000 | Potential conversion income |
| After-tax basis | $6,000 | Verify plan documentation |
| 22% federal scenario | $14,960 | Estimate only |
| 5% state scenario | $3,400 | State rules vary |
Avoid shrinking the rollover for withholding without a plan
A direct Roth rollover may offer tax withholding. Money withheld does not reach the Roth IRA and can be treated as a distribution. If the participant is under the applicable age and no exception applies, that withheld amount can also face an additional tax.
Compare paying estimated tax from cash outside the retirement account with withholding from the transfer. Do not convert an amount that leaves the emergency fund unable to cover tax. A smaller partial conversion can be more manageable if the plan allows it.
Inspect the form and the completed return
Form 1099-R can correctly use code G while still showing a taxable amount in box 2a for a rollover to a Roth account. Enter the form exactly, then verify the taxable amount on Form 1040. Compare it with the plan source breakdown.
The conversion can affect Marketplace premium tax credits, Medicare income-related premiums in later years, education credits, and state tax. Model the entire return. If a preparer assumes every code G is nontaxable, ask for the authority and a line-by-line explanation.
- Confirm the Roth destination.
- Obtain the plan source breakdown.
- Estimate total tax before transferring.
- Verify box 2a and Form 1040.
Frequently asked questions
Is a direct 401(k)-to-Roth-IRA rollover taxable?
Pretax amounts are generally taxable as conversion income. Direct processing changes rollover mechanics, not the tax character.
Does Form 1099-R code G make the rollover tax-free?
No. Code G identifies a direct rollover. Box 2a and the source and destination account types determine taxable income.
Is after-tax 401(k) basis taxed again in the Roth rollover?
Documented after-tax basis is generally not taxed again, but earnings and pretax sources can be taxable. Use the plan’s source records.
Should tax be withheld from the rollover?
Using outside cash can keep the full amount in the Roth and avoid a possible taxable distribution of withheld funds. Compare liquidity and tax needs first.
Can I convert only part of the 401(k)?
Some plans allow partial rollovers or source-specific instructions. Confirm plan rules before building a partial-conversion strategy.
What other costs can conversion income affect?
It can affect tax brackets, credits, Marketplace subsidies, state tax, and future Medicare income-related premiums, depending on the year and household.
Sources and review notes
The calculations and scenarios in this guide are original BreadWinnr worked examples. We recalculated each example and checked that its parts match the stated total. Official sources support the financial concepts. Forum links document the reader problem that prompted the guide and are not treated as financial authority.
- IRS Publication 575, rollovers to Roth IRAs
- IRS Instructions for Forms 1099-R and 5498
- Reddit: traditional 401(k) destination confusion
Read our research, testing, corrections, and source policy.
This guide provides general financial education. It does not account for your complete financial, tax, legal, or contractual situation.
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