Study · Every option modeled

We modeled every Roth conversion strategy. Here's how they rank.

We took one retirement balance and ran it through every path — leaving it in a traditional IRA, converting and paying the tax, laddering the conversion over years, and converting with a deduction offset — with identical returns and the same retirement income. Even assuming deductions cover only 65% of the conversion tax, the gap between the best and worst can top $1.8 million. Below: each strategy ranked, the pros and cons, and the exact scenarios where each one fits — all reproducible on your own numbers in the calculator.

By Casmir Mason — family-office CFO
Updated June 2026 · 2026 tax year
Educational — not tax advice
The short version

Every path below starts with the same dollars. The only thing that changes is how much tax you pay, and when — and because tax paid is money that stops compounding, small differences become enormous over decades. Ranked best-to-worst for a high earner who converts while still working (the calculator's default): 1) Convert with a deduction offset, 2) Convert over several years (laddered), 3) Leave it in the traditional IRA/401(k), 4) Convert in one lump at peak-income rates. Yes — the naive lump conversion finishes last, behind doing nothing. That's the whole lesson: converting only pays if you control what the conversion costs, by timing it into low-income years or by offsetting the tax. Don't take our word for it: run your own numbers.

How we ran this study. Same inputs across all four paths — a $500,000 balance converted at age 55 while still earning $250,000, an 8% annual return, and $5,500/month of after-tax income from age 65 to 90, using 2026 federal (MFJ) brackets. We compare on a total-value basis (the balance left plus the after-tax income already withdrawn), so no path gets credit for tax it still owes. The offset path assumes same-year deductions absorb 65% of each laddered slice's conversion tax — a realistic figure rather than the theoretical 100%, and adjustable from 0–100% in the calculator. One boundary to keep in view: the offset path models the tax effect only — the outside capital (which must be personal, non-IRA money), fees, returns, and risk of the deduction-generating investment sit outside the model (see the honest caveat under #1). Every figure is reproducible in the calculator at its default settings — treat it as an illustration of the mechanics, not a projection for your situation.

The test: same money, four paths

Imagine a $500,000 traditional IRA, an 8% return, and a goal of $5,500/month of after-tax income from age 65 to 90 — converting at 55 while still earning $250,000. That single starting point leads to wildly different ending values depending only on how you handle the conversion tax. At the calculator's defaults the spread is roughly $3.1M for the best path versus $1.3M–$1.7M for the rest. Your figures will differ, which is exactly why you should model your own.

Why the gap is so large. Tax you pay at conversion is money that leaves the account and never compounds again. Keep that bill small, and decades of tax-free growth do the rest. The strategies below are really just four different answers to one question: how little tax can you legally pay on the way in?

The ranking at a glance

RankStrategyConversion taxComplexity / riskBest for
#1Convert + deduction offsetLow (model assumes a 65% offset)HighHigh earners who can use alternative-investment deductions
#2Laddered (multi-year) conversionLow–moderateLowPeople with low-income years before RMDs
#3Leave it traditional$0 now, taxed laterVery lowLower future bracket, or near-term spending
#4Lump conversion at high incomeHigh, at peak ratesLowAlmost no one — unless the year is genuinely low-income

Ranking reflects long-run after-tax value when converting in a high-income year (the model's default). Timing can reorder it — a lump conversion in a genuinely low-income year, paid from outside funds, can jump to second. See the scenarios below.

#4 — Convert and pay the tax (lump, at high income)

Convert the whole balance in one year while still earning, and pay the resulting tax at your peak marginal rates. In the model this is the worst path — it even trails doing nothing.

Why it loses: a $500,000 conversion stacked on a $250,000 salary is taxed largely in the 32–35% brackets (about $180,000 with state), and that money leaves the account on day one and never compounds again. Meanwhile the leave-it path defers everything and gets taxed in retirement at far lower effective rates.

When it flips: execute the same lump conversion in a genuinely low-income year — a gap year, a sabbatical, a business loss — and pay the tax from outside funds, and this path can jump to second place. The strategy isn't bad; converting at the wrong time is. (Paying the tax from the IRA also shrinks the engine and can trigger penalties under 59½.)

#3 — Leave it in your IRA / 401(k)

The default. Do nothing, keep deferring, and pay ordinary income tax on every dollar when you withdraw. At the model's assumptions it beats a badly-timed lump conversion — deferral is genuinely valuable.

Pros: zero effort, zero tax today, full balance keeps compounding (pre-tax); withdrawals in retirement stack on lower income, at lower rates.
Cons: required minimum distributions starting at 73 force taxable income whether you need it or not; withdrawals stack on your other income at your future marginal rate; large balances can trigger Medicare IRMAA surcharges; the entire balance is a future tax liability you don't control — and it still trails every well-executed conversion path.

When it makes sense: you genuinely expect a much lower tax bracket in retirement, you'll spend the money within a few years, or you'll leave it to charity (which pays no income tax on it).

#2 — Convert over several years (laddered)

"Bracket filling." Convert a slice each year — just enough to reach the top of a target bracket without spilling into the next — spreading a large balance across several years.

Pros: keeps each year's slice in lower brackets, so the blended tax is meaningfully lower than a lump; flexible (adjust yearly); no special investments required; pairs perfectly with early-retirement "gap years" before Social Security and RMDs begin.
Cons: takes discipline over several years; the un-converted balance keeps growing (and is taxed later); benefit shrinks if you have no low-income years to exploit.

When it makes sense: for most people, this is the practical winner. If you have a few lower-income years — especially early retirement — laddering captures most of the benefit of converting with none of the complexity of an offset.

#1 — Convert with a deduction offset

Generate large, legitimate tax deductions in the same year as each conversion, so the deductions absorb most of the conversion income. Our model assumes a realistic 65% offset applied to a laddered conversion — typical deals don't cover everything, though careful allocation and structuring can push the offset toward 100%. Even at 65%, this is the path that produced the standout result in the chart — because when most of the conversion tax stays invested, very little leaves the account.

Pros: by far the highest after-tax value in the model; nearly the entire balance keeps working; tax-free growth and withdrawals; no RMDs; no IRMAA on Roth withdrawals.
Cons — and they're real: it requires putting personal, non-IRA capital into deduction-generating investments such as oil & gas working interests (intangible drilling costs under IRC §263(c)) or leveraged real estate in a self-directed IRA — the deductions only work if the investment sits on your personal return, not inside a retirement account. Those investments carry genuine risk, including loss of principal, and add complexity and cost. The tax win only matters if the underlying investment is sound.

When it makes sense: high earners in a high-tax year who already want exposure to these asset classes and have the capacity and risk tolerance to do them well — ideally alongside a CPA. It is the most powerful option and the one that demands the most diligence. See how the offset strategies work →

The honest caveat. "Wins by millions" is true in the model and assumes the offsetting investment performs. Never let a tax tail wag the investment dog — the deduction is only worthwhile if you'd be comfortable owning the investment on its own merits.

Which one fits your situation?

Your situationStrongest fit
Early-retirement gap years before Social Security / RMDsLaddered (#2)
Still earning a high income; want maximum impact and can use alt-investment deductionsOffset (#1)
One unusually low-income year + cash to pay the taxLump (#4 — jumps the ranking here)
Can't pay the conversion tax from outside the accountLaddered (#2) or wait
Expect a much lower bracket later, or need the money soonLeave it (#3)
Plan to leave the account to charityLeave it (#3)
Still working at a high income, no appetite for alt investmentsWait, then ladder (#2) — don't lump-convert now

What to do now

  1. Know your bracket — this year and projected. The whole decision hinges on your rate now versus later.
  2. Model it. Put your real numbers into the calculator and compare all four paths and the monthly income each could fund.
  3. Find your low-income windows. Early retirement, a sabbatical, or a down business year are the cheapest times to convert.
  4. Decide if the offset is for you. If you already want energy or real-estate exposure and can tolerate the risk, read the offset strategies and advanced guide.
  5. Confirm with a CPA before converting — sizing, timing, and the pro-rata rule all matter, and a conversion can't be undone.
See it on your numbersOpen the free calculator →

Frequently asked questions

For high earners who can use it, converting with a same-year deduction offset produces the highest after-tax value because little or no conversion tax leaves the account — so the full balance keeps compounding tax-free. But it requires deduction-generating investments that carry real risk. For most people without that appetite, a laddered (multi-year) conversion done in lower-income years is the next best and far simpler. The right answer depends on your bracket, time horizon, and whether you can pay the tax from outside funds — model it in the calculator.
Spreading a conversion over several years ("bracket filling") usually beats a single lump conversion because each year's slice can stay in lower tax brackets, lowering the blended rate. A lump conversion can still make sense if you have a single low-income year or want it finished. The savings from laddering are largest when you have early-retirement years before Social Security and RMDs begin.
Leaving it traditional is simplest and can be right if you expect to be in a much lower tax bracket in retirement or will need the money soon. But traditional balances face required minimum distributions, fully taxable withdrawals that stack on other income, and can raise Medicare IRMAA surcharges. Over a long horizon, that usually trails a well-timed conversion.
Because the study converts in a high-income year: the whole balance is taxed largely at 32–35% on top of a $250,000 salary, and that tax leaves the account and never compounds again. Deferring instead means withdrawals are taxed later, stacked on much lower retirement income. The same lump conversion executed in a genuinely low-income year, with the tax paid from outside funds, can jump to second place — timing is most of the game.