THE BUCKEYE RETIREMENT BRIEF
Plain talk on taxes, investing, and retiring well in Ohio
Issue: June 29, 2026 | JCS Retirement Tax Advisors
The Conversion Window, and the Cliff at Its Edge
What a Roth Conversion Window Really Is
A Roth conversion moves money from a traditional IRA into a Roth, and you pay the tax on it now instead of later. The window is the stretch of years when your income is low enough that paying that tax actually makes sense. For most retirees it opens the day the paycheck stops and closes when Social Security and required withdrawals begin.
Why Ohio Makes This Easier
Ohio is a friendly place to do this. The state runs a flat 2.75% income tax on income over $26,050, and it does not tax Social Security at all. So the state cost of a conversion is low and easy to predict. The catch is not in Columbus. It sits in the federal Medicare rules.
How the Cliff Works
When you convert, the amount gets added to your income for the year. That raises your Modified Adjusted Gross Income, which is the number Medicare watches. In 2026 the first IRMAA surcharge kicks in once that income passes $109,000 for a single filer or $218,000 for a married couple filing jointly. Go one dollar over the line and you owe the full surcharge. Medicare also looks back two years, so a conversion you do in 2026 shows up on your 2028 premiums.
A Simple Example
Picture a married couple in Delaware County, both 63, retired early with about $1.2 million sitting in traditional IRAs. Social Security has not started, and required withdrawals are still years off. Their income this year is low. They convert just enough to fill the room under the $218,000 line, then they stop. They pay Ohio's flat 2.75% and a modest federal rate now. They shrink the IRA balances that would later force big taxable withdrawals. And they keep their 2028 Medicare premiums clean. The same couple, careless about that line, converts $30,000 too much and hands Medicare an extra surcharge for the privilege.
The Whole Idea
A conversion lets you pick the year you pay the tax instead of letting the IRS pick it for you. The window is real, but it is narrow, and the IRMAA cliff sits right at the edge of it. Knowing where that line falls in a given year is the kind of thing worth having someone watch for you.
STILL WORKING? FILE THIS AWAY
If you are still earning and stacking up 401(k) balances and equity comp, your best conversion years have not arrived yet. They usually show up in the gap between your last paycheck and your first Social Security check. So resist the urge to push every dollar into Roth today. Keep some traditional balance on the board. That tax-deferred money is exactly what you will want to convert later, on purpose, in a low-income year you control.
Worth a Read
How Retirees Can Manage Income to Avoid Higher IRMAA Brackets (Define Financial). A clear walk through the Medicare surcharge tiers and how income decisions trip them.
2026 Tax Strategies with Roth Conversions (Mercer Advisors). A solid overview of timing conversions across several years rather than all at once.
The New $6,000 Senior Bonus Deduction (Kiplinger). The new deduction for filers 65 and older, including the income levels where it fades out.
Ohio Moves to a Flat Tax in 2026 (Otium Financial Planners). What Ohio's flat 2.75% rate means for retirees and working households alike.
If you are sitting on a large traditional IRA and you are somewhere in that pre-Medicare stretch, it is worth mapping out your conversion years before they slip past. No pressure and no pitch. If you want a second set of eyes on where your line falls this year, that is what we are here for.
Jesse Stacy MTAX, CFP®, EA
JCS Retirement Tax Advisors
For education only. This is general information, not personal tax, legal, or investment advice. Figures reflect 2026 rules and can change.