Roth Conversion Ladder: Step-by-Step Retirement Tax Strategy

A Roth conversion ladder means moving a slice of your traditional IRA (or a 401(k) rolled into an IRA) to a Roth IRA every year, with each slice sized to fill a low tax bracket. You pay ordinary income tax on each conversion in the year you make it, but no 10% penalty. The ladder does two jobs: for early retirees, each conversion can be withdrawn penalty-free once it has aged five tax years, which opens retirement money before 59½; for everyone, it shifts pre-tax savings into tax-free Roth money during the low-income years between retirement and Social Security and required minimum distributions (RMDs).

This guide covers the five-year mechanics, how much to convert each year with the 2026 brackets, the conversion strategies that work alongside the ladder, and the rules that make conversions more expensive than they look. To price a specific conversion, use the Roth conversion calculator.

How a Roth conversion ladder works

Three rules from the tax code make the ladder possible:

1. Conversions are taxed, not penalized. The amount converted is ordinary income for the year it leaves the traditional IRA. A direct conversion is not subject to the 10% early-distribution tax, whatever your age.
2. Roth withdrawals come out in a fixed order. Under 26 U.S.C. §408A(d)(4)(B), withdrawals are treated as coming first from your regular contributions, then from conversions on a first-in, first-out basis (the taxable part of each conversion first), and only then from earnings.
3. Each conversion has its own five-year clock. Under §408A(d)(3)(F), if you withdraw converted money within the five-tax-year period beginning with the year of the conversion and you are under 59½, the 10% additional tax applies to the part that was taxable when converted. The clock starts January 1 of the conversion year, so a conversion in December 2026 is seasoned on January 1, 2031. After 59½ the clock no longer matters for converted amounts.

Earnings are different: they generally come out tax-free only after you are 59½ and your first Roth IRA has been open five tax years. A ladder therefore spends the converted principal, not the growth.

A ladder for an early retiree

A married couple retires at 50 with a large traditional IRA, plans to spend $60,000 a year, and has no other income. Each year they convert $60,000:

From 2031 on, each year's spending comes out of the conversion made five years earlier, while they keep converting $60,000 a year to keep the ladder going.

The tax on each rung is small. With the 2026 joint standard deduction of $32,200, a $60,000 conversion leaves $27,800 of taxable income: 10% on $24,800 ($2,480) plus 12% on $3,000 ($360) = $2,840, or 4.7% of the amount converted (brackets from Rev. Proc. 2025-32).

Bridging the first five years

Nothing on the ladder is available for the first five years, so you need another source for that gap:

• Taxable brokerage savings. Selling long-term holdings may cost little: married couples with taxable income under $98,900 in 2026 pay 0% on long-term gains. Conversions count toward that income, so balance the two.
• Roth IRA contributions you made earlier. Regular contributions come out first and can be withdrawn at any age without tax or penalty.
• The age-55 rule. If you leave your employer in or after the year you turn 55, withdrawals from that employer's 401(k) are exempt from the 10% penalty. Rolling that 401(k) into an IRA ends the exception.
• Substantially equal periodic payments under §72(t). These avoid the penalty but lock you into a fixed withdrawal schedule for at least five years or until 59½, whichever is later.

IRA withdrawal tax rules and penalties covers each exception in detail.

How much to convert each year

The usual target is to convert until your taxable income reaches the top of a chosen bracket, typically 12%, 22%, or 24%. These are the 2026 bracket tops (Rev. Proc. 2025-32):

Bracket tops are taxable income. Add your deductions to see how much gross income, conversions included, fits under each one. With the standard deduction and no other income:

At 65 and older, the standard deduction rises by $2,050 for a single filer and $1,650 per spouse, and through 2028 each person 65 or older can also deduct up to $6,000 more, phased out above $75,000 of modified AGI ($150,000 joint). The phase-out means a large conversion can shrink that deduction; the senior deduction guide shows how much.

Worked example: a couple at 60 filling the 12% bracket. They have a $30,000 pension and no other income. Room to the top of 12% is $100,800 + $32,200 − $30,000 = $103,000 of conversion. Their taxable income becomes $100,800, and the tax is 10% × $24,800 + 12% × $76,000 = $2,480 + $9,120 = $11,600, an average of 11.3% on the amount converted. Going to the top of the 22% bracket would add another $110,600 of conversion at 22%, or $24,332 of tax.

Watch your capital gains when you fill the bracket

For joint filers, the 0% rate on qualified dividends and long-term gains ends at $98,900 of taxable income, just below the top of the 12% bracket. Conversion income is stacked first, so it can push investment income out of the 0% band.

A couple has $70,000 of ordinary taxable income and $20,000 of qualified dividends: $90,000 in total, all dividends taxed at 0%. Converting $10,000 raises ordinary income to $80,000 (+$1,200 at 12%) and lifts the dividends to $80,000 through $100,000, so $1,100 of them now sits above $98,900 and is taxed at 15% (+$165). The conversion costs $1,365. On the last $1,100 converted, the rate is 12% + 15% = 27%. How dividends are taxed explains the stacking.

Conversion strategies beyond the basic ladder

Convert in low-income years

The cheapest conversions happen in years when your other income drops:

• The gap between retirement and claiming Social Security, especially if you delay benefits to 70. When to claim Social Security covers the trade-off of living on IRA withdrawals while you wait.
• A year with a job loss, sabbatical, or business loss.
• A year with large itemized deductions, such as medical expenses above 7.5% of AGI or a large charitable gift bunched into one year.

Convert after a market drop

A conversion is taxed on the value of what you move. If an account holding 1,000 shares falls from $100,000 to $75,000, converting the same shares in the 22% bracket costs $16,500 instead of $22,000, and any recovery happens inside the Roth. The catch: a conversion made in 2018 or later cannot be recharacterized (IRS Publication 590-A), so if prices keep falling after you convert, you still owe tax on the higher value.

Time conversions around a move

If you plan to move from a state with an income tax to one without, waiting until after the move removes state tax from the conversion. Federal law (4 U.S.C. §114) bars your former state from taxing IRA distributions you receive as a nonresident. If you are moving the other way, convert before you leave.

Convert to protect a surviving spouse

When one spouse dies, the survivor files as single from the year after the death (unless they have a dependent child), with brackets about half as wide, while the IRA and its RMDs pass to them intact. In 2026, $120,000 of taxable income costs $15,824 in federal tax on a joint return but $21,398 on a single return, $5,574 more on the same income. Converting while both spouses are alive moves money out of that future single-filer bracket.

Convert for your heirs

Most non-spouse beneficiaries must empty an inherited IRA within 10 years. Withdrawals from an inherited traditional IRA are taxed at the heir's rate, often in their peak earning years; withdrawals from an inherited Roth IRA are generally tax-free. If your heirs are likely to be in a higher bracket than you, converting at your rate lowers the family's total tax. The inherited IRA RMD calculator shows what heirs would have to withdraw.

Phases of a typical conversion plan

What limits the conversion changes as you age:

Social Security: the tax torpedo

Once you claim benefits, extra income can make more of them taxable (IRS Publication 915). In the range where benefits are being phased into tax at 85%, a $1,000 conversion adds $850 of taxable benefits, so $1,850 of income is taxed: in the 22% bracket, that is a 40.7% marginal rate. Converting before you claim, or keeping conversions below the range where the phase-in happens, avoids it. How Social Security benefits are taxed has the thresholds.

Medicare IRMAA

Medicare Part B and Part D premiums rise once modified AGI from two years earlier passes $109,000 single or $218,000 joint, for 2026 premiums (CMS). A conversion at 63 can raise your premiums at 65. Each tier is a cliff, so a conversion that crosses one by $1 costs the full surcharge for that year; the MAGI calculator shows where you sit.

ACA premium tax credits

If you buy marketplace coverage before Medicare, conversion income counts toward the household income that sets your premium tax credit. For 2026 coverage, a household above 400% of the federal poverty line gets no credit at all, so one conversion can cost the whole subsidy. The ACA premium tax credit calculator and the year-end tax moves checklist show where the line falls.

Net investment income tax

A conversion is not net investment income, but it raises modified AGI. If your MAGI crosses $200,000 single or $250,000 joint, the 3.8% tax applies to the smaller of your net investment income or the amount your MAGI exceeds the threshold (IRS Topic 559).

Rules and mistakes that make conversions cost more

• Take your RMD first. A required minimum distribution cannot be rolled over or converted (26 U.S.C. §408(d)(3)(E)), and the first dollars out of an IRA in an RMD year count toward the RMD. RMDs start at 73, or 75 if you were born in 1960 or later. Roth IRAs have no RMDs during the owner's life (§408A(c)(4)).
• Use QCDs to free up bracket room after 70½. A qualified charitable distribution of up to $111,000 in 2026 counts toward your RMD but stays out of income (IRS Notice 2025-67), leaving more of the low brackets for conversions.
• Convert by December 31. A conversion counts in the year the money leaves the traditional IRA, and there is no extension to April.
• Pay the tax from outside the IRA. Tax withheld from a conversion is a distribution: before 59½ it is also subject to the 10% additional tax, and it shrinks the amount that grows tax-free.
• Cover the tax during the year. A large conversion can trigger an underpayment penalty. You are safe if withholding and estimated payments cover the smaller of 90% of this year's tax or 100% of last year's (110% if last year's AGI was over $150,000) (Form 1040-ES).
• Check for after-tax basis. If any of your traditional, SEP, or SIMPLE IRAs hold nondeductible contributions, each conversion is taxed pro rata across all of them, reported on Form 8606. You cannot convert only the after-tax dollars. The backdoor Roth calculator applies the pro-rata rule.
• Count your state tax. Most states with an income tax tax conversions too, so your real rate is federal plus state.

When a conversion ladder is not worth it

A conversion only wins if the tax you pay now is lower than the tax you or your heirs would pay later. With the same tax rate on both ends, converting and not converting leave the same after-tax amount: $100,000 converted at 22% leaves $78,000 in the Roth, and $100,000 left in a traditional IRA and withdrawn later at 22% also leaves $78,000 after any growth is applied equally to both. The Roth comes out ahead when your future rate is higher, when you pay the conversion tax from outside money, or when RMDs, Social Security taxation, IRMAA, or a single-filer survivor would push later withdrawals into higher brackets. If you expect a lower rate in retirement, plan to leave the money to charity, or would have to pay the tax from the IRA itself, converting less, or not at all, may be better.

The Roth conversion calculator compares after-tax wealth with and without a conversion for your inputs, and the Retirement Withdrawal Planner spreadsheet fills the bracket you choose each year and compares the result with not converting.