The Roth Conversion Ladder

For a calendar-year taxpayer, a conversion's five-tax-year period starts January 1 of its conversion year and clears January 1 of year + 5. A conversion at any time in 2026 clears that period on January 1, 2031; January and December conversions in the same year have the same legal clock. Moving the transaction earlier within that year does not advance the clearance date.

Before age 59½, a nonqualified Roth withdrawal allocated to a recent conversion's taxable portion can trigger the 10% additional tax, unless an exception applies. The conversion principal is not taxed as income a second time. The age-59½ exception removes that additional tax even if the conversion's clock is unfinished.

Age 59½ alone does not make Roth earnings tax-free. A qualified distribution also requires the separate five-tax-year period beginning with the first tax year of funding any Roth IRA for you. Other qualifying events and additional-tax exceptions have their own conditions. This tool does not establish qualification or model exceptions.

This illustration starts conversions in retirement Year 1; it does not plan pre-retirement conversions. Retirement and transactions are treated as the start of a calendar year. Whole-year age labels are an approximation: no date of birth is entered and no exact 59½ date is calculated.

Budget years = ceiling(59.5 − retirement age)
Target rungs for a positive spending target = max(0, budget years − 5)

The last partial year before 59½ receives a full annual spending budget. That deliberately overstates a partial-year need; the model does not project life after this short window. At a retirement-age label of 50, it shows 10 budgets, with five conversions in Years 1–5 clearing in Years 6–10. At age 58, it shows two budgets and no new conversion that clears within them.

Each target rung equals the annual spending target. It is reduced if the modeled pre-tax balance is insufficient. Conversions occur before that year's assumed growth. No new savings or other Traditional withdrawals are added. The final column is cumulative converted principal, not a Roth balance or withdrawal ledger.

Because conversion tax is paid separately, a $50,000 principal target calls for a $50,000 conversion, not a larger conversion netted down by tax. With no other income, Single filing, full basic deduction eligibility and the 2026 brackets: $50,000 − $16,100 = $33,900 taxable income; $12,400 × 10% + $21,500 × 12% = $3,820 estimated federal tax.

At a 0% return, five such conversion years require $250,000 for spending plus $19,100 for conversion taxes: $269,100 in initial bridge funds. This is an example, not a typical tax bill or a recommendation.

For the first min(5, budget years) years, the model subtracts spending and that row's conversion tax at the start of each year, then grows the remaining bridge funds. No borrowing or negative cash balance is assumed. A required-starting-funds calculation discounts those same annual costs at the entered return. Later conversion taxes are displayed separately but not budgeted in this initial check.

The same 2026 basic standard deduction and ordinary brackets are held fixed in every illustrated year. Other income, investment income from bridge funds, credits, itemized/extra deductions, state taxes, ACA effects, Social Security taxation, Medicare IRMAA and future law/indexing are omitted. The calculation is not a tax return and does not use the IRS Tax Table's income bands.

Nonqualified Roth IRA distributions generally come from regular contributions first, then conversions and certain rollovers by year, taxable portion first within a year, then earnings. The rules aggregate your Roth IRAs; a separate account does not let you choose a younger or older rung. Remaining regular-contribution basis can generally be withdrawn without income tax or the additional tax.

A total Roth balance does not identify those categories. This model therefore does not count existing Roth funds as bridge cash, add Roth growth to principal, or certify the amount you may withdraw. Even a seasoned rung can fund spending only if principal remains and the assets are there; market losses and prior withdrawals matter.

Only eligible money may be converted. Workplace-plan distribution restrictions, required distributions, inherited accounts, SIMPLE IRA restrictions and nondeductible IRA basis need separate treatment. The tool assumes eligible, fully taxable funds; it is not an eligibility or pro-rata calculator.