When Should Ohio Retirees Consider a Roth Conversion?
Quick answer: A Roth conversion moves money from a traditional IRA or 401(k) to a Roth IRA, paying ordinary income tax on the converted amount now in exchange for tax-free withdrawals later. For Ohio retirees, Roth conversions can make sense in lower-income years before Required Minimum Distributions begin, when leaving Roth assets to heirs is part of the estate plan, or when the conversion year's tax bracket is meaningfully lower than expected future brackets. The decision involves coordinating federal taxes, Ohio taxes, Social Security taxation, Medicare IRMAA tier impacts, and long-term return expectations. There is no universal right answer — conversions can be appropriate for one retiree's situation and inappropriate for another's. This article is educational; specific Roth conversion advice requires a qualified tax professional.
Key Takeaways
- A Roth conversion exchanges current taxes for future tax-free Roth withdrawals.
- The decision depends on the conversion year's tax bracket compared to expected future brackets, the time horizon for the conversion to "break even," and how the conversion affects other parts of the tax picture.
- Conversions are taxable in both federal AGI and Ohio AGI in the year they occur.
- Roth conversions can affect Medicare IRMAA tiers two years after the conversion year, increasing Medicare premiums temporarily.
- Conversions can also affect the federally taxable portion of Social Security benefits in the conversion year.
- The "best" years for conversions are typically lower-income years — between retirement and Social Security claiming, or between Social Security and RMD age.
- Once made, a Roth conversion generally cannot be reversed under current tax law.
Table of Contents
- What a Roth Conversion Is
- When a Roth Conversion May Be Worth Considering
- When a Roth Conversion May Not Make Sense
- How a Roth Conversion Is Taxed in Ohio
- How Conversions Affect Medicare IRMAA
- How Conversions Affect Social Security Taxation
- Multi-Year Roth Conversion Strategy
- Roth Conversions and Estate Planning
- Common Mistakes to Avoid
- Frequently Asked Questions
What a Roth Conversion Is
A Roth conversion is the process of moving assets from a traditional retirement account — a traditional IRA, traditional 401(k), 403(b), or similar tax-deferred account — into a Roth IRA. The converted amount is taxed as ordinary income in the year of the conversion. In exchange, the assets grow tax-free in the Roth IRA going forward, and qualified Roth withdrawals are tax-free in retirement.
The mechanic in plain terms: you pay tax now on money that would otherwise be taxed when you withdrew it in retirement. The trade-off is paying tax at today's rates instead of tomorrow's, and giving up the ability to keep those dollars growing tax-deferred.
A few structural points worth understanding before evaluating any conversion:
Conversions are taxable as ordinary income in both federal AGI and Ohio AGI for the year they occur. There's no preferential rate on a conversion the way there might be on long-term capital gains.
Conversions generally cannot be undone under current tax law. The "recharacterization" provision that previously allowed conversions to be reversed was eliminated. Once you convert, that decision is essentially permanent.
Conversions count toward income for the year — affecting your tax bracket, the federally taxable portion of Social Security, eligibility for various credits and deductions, and your Medicare IRMAA tier two years later.
Conversions don't satisfy Required Minimum Distributions. If you're at RMD age, you must take your RMD before or alongside a conversion — RMDs themselves can't be converted.
This article is part of my broader guide on how to plan a tax-efficient retirement in Ohio, which covers how Roth conversions fit with the rest of the retirement tax picture.
When a Roth Conversion May Be Worth Considering
Roth conversions tend to be most valuable in specific situations. This isn't an endorsement of conversions in these situations — it's a description of the circumstances under which the analysis is more likely to favor them.
When current tax brackets are meaningfully lower than expected future brackets. This is the foundational case for Roth conversions. If you can pay tax now at a lower rate than you'd pay later, the conversion produces a net tax savings (assuming the math works on the time horizon).
In the gap years between retirement and Social Security claiming. Many retirees experience their lowest taxable income in the years between retirement and starting Social Security. Earned income has stopped, Social Security hasn't started, and RMDs haven't begun. This window can be a strategic time for conversions.
In the gap between Social Security claiming and Required Minimum Distributions starting. For retirees who claim Social Security at full retirement age but delay tapping retirement accounts, there's another window where income may be moderate enough to make partial conversions sensible.
When leaving Roth assets to heirs is part of the estate plan. Heirs who inherit Roth IRAs generally receive tax-free distributions (subject to current inheritance rules). For retirees who don't expect to need the converted assets themselves, conversions can be a way to pass on tax-free wealth.
When current legislation or tax law expectations suggest higher rates ahead. If a retiree expects federal income tax rates to rise during their retirement — whether from legislative changes, RMDs pushing them into higher brackets, or other factors — converting at today's rates may capture savings.
When there's room in the current tax bracket. "Filling up" a lower bracket with a partial conversion can capture conversion benefits at the marginal rate of that bracket, rather than spilling into a higher bracket.
Even in these situations, the conversion still has to pass the math test — the analysis depends on time horizon, expected returns, and the rest of the household tax picture.
When a Roth Conversion May Not Make Sense
Conversions aren't always appropriate. Several patterns suggest a conversion may not produce the expected benefit.
When the conversion year's tax bracket is higher than the expected future bracket. If you're paying tax at a higher rate today than you'd pay later, the conversion produces a net tax cost rather than a savings.
When the time horizon to "break even" is too long. Conversions require time for the tax-free growth to recover the upfront tax cost. A retiree in their late 80s converting a large amount may not have the runway for the math to work, even if the bracket comparison looks favorable.
When the conversion would push you into a much higher tax bracket. Converting an amount that spills into a substantially higher bracket can erase the conversion benefit. Partial conversions sized to "fill" a bracket without spilling into the next one are usually preferable.
When the conversion would trigger a Medicare IRMAA tier increase that wasn't planned for. A large conversion in one year can push income above an IRMAA threshold, increasing Medicare premiums for the two-year lookback period.
When the conversion increases the federally taxable portion of Social Security to its maximum. Once Social Security taxation is fully maxed out, additional conversion income produces incrementally less benefit per tax dollar paid.
When liquidity to pay the conversion tax is limited. The conversion is most efficient when the tax can be paid from taxable account funds, not from the converted amount itself. Paying conversion tax from the IRA reduces the amount that ends up in the Roth and weakens the conversion math.
When tax law is expected to fall significantly. If rates are expected to drop substantially during retirement, converting at today's higher rates loses some of its appeal.
The conversion decision is rarely obvious. A conversion that looks great in isolation can look worse once Medicare IRMAA, Social Security taxation, and Ohio tax effects are factored in.
How a Roth Conversion Is Taxed in Ohio
For Ohio retirees, a Roth conversion is taxed at three levels: federal, Ohio state, and potentially school district.
Federal taxation. The converted amount is included in federal taxable income for the year and taxed at ordinary income rates. For most retirees, this means the conversion is taxed at the marginal federal rate where the conversion lands in the bracket structure.
Ohio taxation. Because Ohio starts its income tax calculation with federal adjusted gross income, the conversion flows into Ohio AGI and is taxed at Ohio's regular rates. The Ohio retirement income credit doesn't apply to Roth conversion income, since conversions aren't treated as qualifying retirement income for that credit.
School district income tax. If you live in an Ohio school district that imposes income tax using the "traditional" tax base, the conversion may also be subject to school district tax. Districts using the "earned income" base generally don't include conversion income. Verify your district's treatment with the Ohio Department of Taxation or a tax professional.
The combined Ohio-level tax on a conversion (state plus school district where applicable) is typically modest compared to federal taxation, but it does affect the math. For Columbus-area retirees in districts with traditional-base school taxes, the school district layer is one of the most-overlooked elements of conversion planning.
Practical implication for withholding. Roth conversions don't have automatic withholding the way pension or distribution payments do. You may need to make estimated tax payments to cover federal and Ohio liability from a conversion, or increase withholding from other income sources. Failing to plan for the tax can produce an underpayment penalty at filing time.
How Conversions Affect Medicare IRMAA
This is one of the most consequential and least-understood interactions in Roth conversion planning.
Medicare IRMAA — the Income-Related Monthly Adjustment Amount — is a surcharge on Medicare Part B and Part D premiums for retirees whose income exceeds certain thresholds. IRMAA is based on Modified Adjusted Gross Income (MAGI) from two years prior. A conversion this year affects Medicare premiums two years later.
The interaction matters because:
A large conversion can push you into a higher IRMAA tier for the two-year lookback period. The premium increase isn't permanent — it adjusts year-over-year based on income from two years prior — but it can be significant.
IRMAA tiers are based on cliff thresholds, not gradual phase-ins. Crossing a threshold by even a small amount can trigger the full higher premium tier. Conversions sized to stay below an IRMAA threshold can avoid this.
Both spouses' Medicare premiums can be affected for households filing jointly, doubling the impact in many cases.
The federal premium increase is in addition to any conversion tax cost. When evaluating whether a conversion produces net savings, the IRMAA impact has to be included.
For retirees enrolled in Medicare, multi-year conversion planning often involves sizing conversions to stay within (or strategically across) IRMAA thresholds rather than maximizing the conversion amount in any single year.
How Conversions Affect Social Security Taxation
For retirees receiving Social Security, conversions can affect how much of Social Security becomes federally taxable.
Federal taxation of Social Security depends on "combined income" — a calculation that adds half of Social Security benefits to other taxable income. As combined income rises, the share of Social Security benefits that becomes taxable increases, up to a maximum of 85% of benefits.
A Roth conversion adds to other taxable income for the year, which:
- May push more of your Social Security benefits into the taxable category
- May increase the share of Social Security that's taxable up to the 85% cap
- Doesn't affect Ohio taxation of Social Security (Ohio doesn't tax Social Security regardless)
For retirees who've already maxed out Social Security taxation at the 85% level, the conversion doesn't add additional Social Security tax — but it does add federal tax on the conversion itself. For retirees below the 85% cap, the conversion produces a "stacking" effect where conversion income pushes additional Social Security into taxation.
This is one reason the gap years before Social Security claiming can be especially attractive for conversions — Social Security taxation isn't yet in the picture.
Multi-Year Roth Conversion Strategy
The most effective Roth conversion approach is usually multi-year rather than one-time.
Why spread conversions across years:
- Smaller annual conversions are less likely to push you into a higher tax bracket
- They reduce the risk of triggering a Medicare IRMAA tier jump
- They limit the impact on Social Security taxation in any single year
- They reduce concentration risk if tax law changes between years
The general approach to multi-year planning:
A retiree begins by identifying the "low-income window" — typically between retirement and the start of Social Security, or between Social Security and Required Minimum Distributions. Within that window, partial conversions are sized to fill a target tax bracket without spilling into a higher one. The conversion amount is selected to stay below the next IRMAA threshold, manage Social Security taxation effects, and produce a tax cost that can be paid from non-converted funds.
The same approach repeats year-over-year, with annual review of the household's tax picture, the conversion math, and any changes in tax law or personal circumstances.
For a household with $1 million in traditional IRA assets, a multi-year conversion strategy might convert $30,000-80,000 per year for 5-10 years rather than converting $500,000 in one year. The lower annual amounts produce meaningfully better results across most scenarios.
Roth Conversions and Estate Planning
Roth conversions interact with estate planning in ways that can favor conversions for some retirees.
Inherited Roth IRAs receive favorable tax treatment. Under current rules, beneficiaries who inherit a Roth IRA generally pay no federal income tax on the distributions, though they may be subject to a withdrawal timeframe under the SECURE Act. The result is that Roth assets passed to heirs can produce tax-free wealth transfer in a way that traditional IRA assets can't.
Traditional IRA inheritance produces taxable income for heirs. Beneficiaries who inherit a traditional IRA pay ordinary income tax on distributions. For high-income heirs, the tax cost can be substantial.
Conversions effectively prepay the heirs' tax. When a retiree converts during their lifetime and pays the conversion tax, they're paying at their (potentially lower) tax rate rather than the heirs' (potentially higher) tax rate. For families where heirs are in higher brackets than the retiree, this can be a significant benefit.
Estate tax considerations apply for larger estates. For federal estate tax purposes, conversions can also help in some scenarios because the tax paid on the conversion reduces the taxable estate.
These estate-related benefits don't apply to every retiree. Heirs in lower brackets than the retiree don't benefit from prepayment. Retirees without estate-tax concerns don't benefit from estate reduction. The estate angle is one factor in conversion analysis, not a universal driver.
Common Mistakes to Avoid
Several patterns come up repeatedly with Roth conversion decisions.
Converting too much in a single year. Large one-year conversions are vulnerable to bracket jumps, IRMAA tier increases, and Social Security taxation effects that erode the conversion's value. Multi-year planning almost always produces better outcomes.
Failing to model the IRMAA effect. Retirees enrolled in Medicare often underestimate how much a conversion can affect their premiums two years later. The IRMAA impact should be modeled as part of the conversion math, not discovered after the premium increase arrives.
Paying the conversion tax from the IRA itself. When tax is withheld from the converted amount, the amount that lands in the Roth is reduced — which weakens the conversion math considerably. Paying the tax from outside funds (taxable account or current income) is generally more efficient.
Converting without checking Ohio implications. Ohio tax and school district tax (where applicable) can add meaningfully to the conversion cost. The full tax picture includes federal, Ohio state, and potentially school district.
Converting without coordinating Social Security claiming. Conversions before claiming Social Security avoid the stacking effect on Social Security taxation. Conversions after claiming Social Security need to account for that interaction.
Failing to take RMDs before converting. For retirees at RMD age, the RMD must be taken before or alongside the conversion. Skipping this step can produce penalty issues.
Underestimating the irreversibility. Conversions can't be undone under current tax law. The decision should be made with the full picture in mind, not based on a partial analysis.
Frequently Asked Questions
What is a Roth conversion? A Roth conversion is the process of moving money from a traditional retirement account (such as a traditional IRA or 401(k)) into a Roth IRA. The converted amount is taxed as ordinary income in the year of conversion. In exchange, the assets grow tax-free in the Roth IRA, and qualified withdrawals in retirement are tax-free.
Are Roth conversions taxable in Ohio? Yes. A Roth conversion is included in federal adjusted gross income and flows into Ohio adjusted gross income. The conversion is subject to Ohio income tax at regular rates and may also be subject to school district income tax depending on your district's tax base.
Can I undo a Roth conversion? Under current tax law, Roth conversions generally cannot be undone. The "recharacterization" provision that previously allowed reversal was eliminated. This is one reason conversions deserve careful analysis before being made.
Will a Roth conversion affect my Medicare premiums? A Roth conversion adds to your income for the year, and Medicare IRMAA is based on income from two years prior. A large conversion can push you into a higher IRMAA tier, increasing Medicare Part B and Part D premiums for the two-year lookback period.
When is the best time for a Roth conversion? There is no universal best time. Conversions tend to be most attractive in lower-income years — between retirement and Social Security claiming, or between Social Security claiming and the start of Required Minimum Distributions. The specific timing depends on your tax bracket, Medicare IRMAA position, Social Security claiming strategy, and other factors that should be reviewed with a qualified tax professional.
Should I convert all my traditional IRA to a Roth at once? Most retirees benefit from spreading conversions across multiple years rather than converting all at once. Smaller annual conversions reduce the risk of bracket jumps, IRMAA tier increases, and Social Security taxation effects. The right multi-year approach depends on your specific situation.
Can I pay the conversion tax from the IRA itself? You can, but it's generally inefficient. Paying tax from the converted amount reduces the dollars that end up in the Roth and weakens the conversion math. Paying from outside funds (a taxable account or current income) produces better results.
Do Roth conversions count toward Required Minimum Distributions? No. Conversions and RMDs are separate. For retirees at RMD age, the RMD must be taken before or alongside the conversion — RMDs themselves cannot be converted to a Roth.
Should I work with a tax professional on Roth conversion decisions? Yes. Roth conversions interact with federal taxes, Ohio taxes, Social Security taxation, Medicare IRMAA, and estate planning in ways that benefit from professional review. A qualified tax professional should be involved in the conversion decision, particularly for conversions of meaningful size.
A Decision That Deserves Time and Analysis
For Ohio retirees, Roth conversions can be one of the more powerful tools in retirement tax planning — but they're not appropriate for every situation. The decision depends on tax bracket comparisons, time horizons, Medicare IRMAA impacts, Social Security taxation effects, Ohio and school district tax implications, and estate planning goals.
The pattern that tends to produce better outcomes: multi-year planning that sizes annual conversions to fit within tax brackets and below IRMAA thresholds, coordinated between a financial advisor and a tax professional, with clear analysis of the conversion math before any single year's decision is made.
For the bigger picture of how Roth conversions fit into the broader tax planning framework for Ohio retirees, see my pillar guide on how to plan a tax-efficient retirement in Ohio.
At Blue Advisors, I work with Columbus-area retirees and pre-retirees to evaluate Roth conversion strategies as part of a coordinated retirement tax plan. I work alongside our clients' tax professionals rather than replacing them — Roth conversion decisions benefit most when an advisor and tax professional are working from the same picture.
Schedule a conversation: If you're an Ohio retiree or pre-retiree thinking through Roth conversion strategy, you can book an introductory call here: calendly.com/jimblue/blue-advisors-meeting.
By James Blue, Fee-Only Advisor | Blue Advisors
James Blue is the founder of Blue Advisors, a fee-only registered investment advisory firm based in Columbus, Ohio, serving retirees, pre-retirees, and busy professionals across Central Ohio and nationally.
This content is provided for informational and educational purposes only and should not be construed as personalized investment, tax, or legal advice. Roth conversion decisions are highly individual and generally irreversible. Tax laws and rules change frequently, and individual tax situations vary significantly. The views expressed are those of the author as of the date published and are subject to change without notice. Blue Advisors is a fee-only registered investment advisory firm and is not a tax preparation firm or law firm. Readers should consult a qualified tax professional, the IRS, the Ohio Department of Taxation, and where applicable an attorney before making tax or financial decisions. Advisory services are offered only pursuant to a written advisory agreement and to clients in the State of Ohio, the Commonwealth of Pennsylvania, and other jurisdictions where Blue Advisors is properly registered or exempt from registration. Past performance is not indicative of future results. Specific dollar thresholds, tax rates, IRMAA tiers, and Social Security taxation thresholds change over time and have been kept general in this article.