How much should you convert to Roth — without jumping a bracket?

The trick to Roth conversions isn’t converting everything — it’s converting just enough each year to fill your tax bracket and stop. Do that for a few years running and you move serious money to tax-free at a rate you chose, instead of the rate RMDs choose for you later. This planner shows the bracket, the headroom, and the multiyear math.

Built on the 2026 federal brackets under the One Big Beautiful Bill Act and Indiana’s 3.000% rate. Conversions are ordinary income — that’s what makes the bracket ceiling the whole game.

Your numbers

Pre-tax retirement balance

Traditional IRA, old 401(k)s, rollovers — the money that’s never been taxed.

Filing status

Taxable income, before any conversion

Line 15 of your 1040 — income after deductions. If you only know your total income, subtract the standard deduction (2026: $16,100 single, $32,200 married filing jointly). Estimates are fine.

Fill up to the top of the

Tax rate you expect in retirement

Your best guess at the federal rate when this money comes out. RMDs and one spouse filing single later often push it higher than people expect.

Expected annual growth

On the invested money, either side of the conversion.

Conversion window

5 years

State tax

Indiana county rate

Every county adds its own rate on top of the 3.000% — it’s on your county’s line of last year’s IT-40, or ask us. 0 to skip.

Your age optional

So we can flag where required minimum distributions land in this plan.

Your conversion plan shows up here.

Enter your balance and income, pick the bracket you’re willing to fill, and we’ll show you how much to convert each year — and what the plan is worth versus doing nothing.

The better path

Convert on the plan

After-tax value in 5 years

The better path

Do nothing

After-tax value in 5 years

Year-one conversion

fills to the bracket top

Converted over the window

Rate paid on conversions

vs. expected later

No headroom in that bracket. Your income is already past the top of the bracket you picked, so there’s nothing to fill. Pick a higher bracket to see the math — or better, bring this to us, because converting on top of your current rate is a different decision than filling below it.

Filling the bracket, year by year

Your taxable income Roth conversion Headroom left unused = the bar’s right edge

Here’s how it lands

The year-by-year numbers ▶

Your moves

Numbers without a next step are just trivia. Here’s what this plan says to do.

Estimate only — a Delta review is required before acting. A conversion is permanent — there’s no undo button since 2018 — and the right amount depends on things this planner can’t see: Medicare premium cliffs, the net investment income tax on your other income, Social Security taxation, and what your heirs’ tax picture looks like. We run the real numbers with you before anything converts.

What this plan assumes — out in the open

2026 federal brackets, held flat for every year of the window. In reality the IRS indexes brackets up each year, which gives you a little more headroom than shown — this estimate is the conservative side.
Your taxable income stays the same each year. A big income swing in either direction changes the annual conversion amount — that’s a recalculation, not a problem.
The conversion tax is paid from cash outside the IRA. That’s the right way to do it. Paying it from the IRA itself shrinks the conversion and, before 59½, adds a 10% penalty on the tax money.
The do-nothing side gets credit for keeping its cash. The taxes you’d have paid stay invested at the same growth rate, untaxed along the way — which slightly flatters doing nothing. If conversions still win, they win honestly.
Your future rate is your pick — applied to every pre-tax dollar at the end of the window. The truth arrives one RMD at a time.
State tax is whatever you enter — Indiana’s 3.000% plus your county’s own rate (every county sets one and they change, so you enter it rather than trust a stale table), or your own state’s combined rate. The plan assumes the same state taxes both the conversion now and the withdrawal later — retiring to another state changes both sides.
Not modeled: Medicare IRMAA surcharges (conversions after 63 can raise premiums two years later), the net investment income tax on your other investment income, Social Security taxation, ACA premium credits, and the pro-rata rule if you have nondeductible IRA basis. Exactly the things a Delta review catches.
Each conversion starts its own five-year clock for penalty-free access to that money before 59½.
RMDs can never be converted. Once yours start (73 if born 1951–1959, 75 if born 1960 or later), the RMD comes out first, then conversions stack on top.

Before you convert a dollar — let Delta size it right.

The bracket math is the easy half. The hard half is what this planner can’t see — Medicare cliffs, your other income, the state you’ll actually retire in, and what your heirs inherit. Conversions are a December decision, and December is exactly when we do this with clients: income known, brackets known, no guessing. Send this over and we’ll tell you the number to convert this year.

Reach your Delta team at (260) 440-2747 or info@deltacpagroup.com and we’ll walk through it with you.

They say the best time to plant a tree is 20 years ago, and the second best is today — Roth conversions work the same way. We are always happy to talk it through.

Thank you,
Amy Grego, CPA Delta CPA Group, LLC · (260) 440-2747