She Retired at 64 With $380,000 in a 401(k) and No Income for Nine Years. She Never Converted a Dollar. Her First RMD Was Taxed at 22%.

A retiree who leaves work at 64 with a $380,000 401(k) balance and no earned income for the next nine years enters what planners call the gap years: the stretch between the last paycheck and the required beginning date when required minimum distributions (RMDs) kick in. An RMD is the amount the IRS forces out of a pre-tax retirement account each year once the required beginning date is reached. In the scenario laid out here, she did nothing during those years and never converted a dollar to a Roth. When RMDs finally began, her first one was taxed at 22%. That outcome was entirely avoidable. Every unused year carried a cost that compounded right alongside her balance.

Timeline: A Nine-Year Window That Was Legally Available

Under SECURE 2.0, the required beginning age depends on birth year: 73 for individuals born between 1951 and 1959, and 75 for those born in 1960 or later. A retiree who left work at 64 and took her first RMD nine years later reached her required beginning date at 73, placing her in the pre-1960 cohort. For someone born in 1960 or later, the same retirement age would open an eleven-year window rather than nine. However long the gap runs, it represents some of the most flexible tax years a retiree will ever occupy, and the value of that flexibility is difficult to recover once forfeited.

What Low-Income Gap Years Actually Look Like on a Tax Return

During those nine years between 64 and 73, she had no wages, no pension, and had not yet claimed Social Security. Her taxable income each year was close to zero. For 2026, the IRS set the single standard deduction at $16,100, and the 22% bracket begins above $50,400 in taxable income. A single filer with no other income can recognize a meaningful amount of taxable income each year and still stay comfortably within the lower brackets. The One Big Beautiful Bill Act (OBBBA) further widened that room by adding a $6,000 deduction for taxpayers age 65 and older, available for tax years 2025 through 2028 and phasing out above $75,000 in modified adjusted gross income (with full elimination at $175,000). That additional shield means a qualifying gap-year retiree has even more capacity to convert pre-tax dollars before crossing the 22% threshold, which makes the forgone years even costlier in retrospect.

Conversion Capacity Does Not Carry Forward

Every year she skipped a conversion, that 12% bracket space expired permanently. Her untouched $380,000 balance kept compounding in the meantime. At an average 6% annual return over those nine years, the account swelled to roughly $642,000 by age 73. When her required beginning date arrived, the IRS Uniform Lifetime Table (divisor of 26.5 at age 73) mandated a first-year RMD of about $24,200. Stacked on top of the maximum Social Security benefit she began collecting at 70, where 85% of benefits are taxable, that mandatory distribution pushed her taxable income past the 12% ceiling of $50,400. The top dollars of her first RMD landed squarely in the 22% bracket, exactly as the math predicted.

What a Conversion Plan Would Have Done

The standard playbook for someone in her position is annual partial Roth conversions sized to the top of a chosen bracket. A conversion moves money from a traditional 401(k) or IRA into a Roth, triggers ordinary income tax on the converted amount, and allows that money to grow and be withdrawn tax-free afterward. Filling the 12% bracket each year for nine years would have shifted a large share of the pre-tax balance into a Roth at a 12% rate, permanently shrinking the pool from which future RMDs are calculated. Those low-tax years between the last paycheck and the first RMD are the whole subject of our free Roth Window guide.

Two operational details matter here. First, pay the tax on each conversion from outside taxable savings rather than from the converted amount itself, so the full converted dollar keeps compounding inside the Roth. Second, coordinate conversions with the Social Security claiming decision, because once benefits begin, more of every conversion dollar gets taxed, and more of Social Security itself becomes taxable. Sequencing matters as much as sizing.

Broader Context

The 10-year Treasury yield reached 5.10% on October 15, 2026, up from roughly 5.00% in mid-September and from 4.67% in late August, after briefly touching a 24-year high of 5.36% on October 7 following renewed fiscal pressures. Separately, the Social Security Administration officially confirmed a 2027 COLA of 3.6% on October 14, 2026, the largest annual increase since 2023. Both developments illustrate the same pressure facing retirees who did not convert during their gap years: as balances grow and benefits adjust upward, the taxable share of retirement income rises mechanically, year after year, with little room left to redirect it.

What the Case Actually Shows

The nine-year window was the cheapest tax environment she would ever occupy. Leaving it untouched concentrated the tax bill into the years when she had the least flexibility, on a balance that had grown according to market returns and RMD schedules rather than any deliberate plan. The gap years do not wait, and their capacity to shelter conversions does not roll over to the following year. Once the required beginning date arrives, the opportunity to act at 12% is gone.

Editor’s note: This article has been updated to reflect the 10-year Treasury yield reaching 5.10% as of October 15, 2026 and briefly touching a 24-year high of 5.36% on October 7; the SSA’s official confirmation of a 3.6% Social Security COLA for 2027, announced October 14, 2026; and the OBBBA senior deduction phase-out ceiling of $175,000 for single filers, which narrows the population of gap-year retirees who receive the full $6,000 benefit.

Contact [email protected] for any questions or corrections.