The Early Retiree and the Roth Conversion Window
Dana, 58, retired last year. She has $1.9 million in a traditional 401(k), $240,000 in a taxable brokerage account with a $90,000 unrealized gain, and $60,000 in a Roth IRA opened 12 years ago. She is not yet 59½ and plans to delay Social Security to 70, when her benefit would be about $4,100/month in today's dollars. Her only income this year is $18,000 of interest and dividends. She wants to convert enough to the top of the 24% bracket and asks whether she should also take withdrawals from the 401(k) to live on. She has no earned income and no pension.
1. Evaluate Dana's plan to convert to the top of the 24% bracket and to fund living expenses from the 401(k) before age 59½.
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Two issues must be separated: the conversion sizing and the pre-59½ withdrawal.
Conversion sizing. Converting to the top of the 24% bracket is a common heuristic but should be tested against her future marginal rate. With $1.9 million growing for roughly 12 years before RMDs begin at 75, and with Social Security at 70 plus future RMDs, her later marginal rate could be 22%–24% or higher depending on balances and filing status. Converting at 24% is reasonable only if her projected future rate is at least that high; if her future rate is lower, she is overpaying. A better approach is a multi-year bracket-filling schedule that models each year's taxable income, IRMAA thresholds, and the Social Security taxation formula (up to 85% of benefits includable). Note that IRMAA is based on MAGI two years prior, so large conversions at 63+ can raise Medicare premiums.
Pre-59½ withdrawals. Distributions from the 401(k) before 59½ are generally subject to a 10% additional tax unless an exception applies. The 72(t) substantially equal periodic payment exception is available but locks her into a schedule for five years or until 59½, whichever is longer - here, until 63½ if she starts now. Alternatives: use the taxable account for living expenses (harvesting gains at 0% or 15% capital gains rates), tap Roth contributions (not earnings) tax- and penalty-free, or use the 'rule of 55' only if she separated from service in or after the year she turned 55 from that employer's plan.
Recommend a written conversion schedule and a spending waterfall, reviewed annually.
2. Dana asks whether converting now reduces her future RMDs and whether she should convert all at once. What is your analysis?
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Yes, conversions reduce future RMDs by shrinking the traditional balance, but the magnitude depends on growth and timing, and a single large conversion is usually the wrong tool.
Analysis:
- RMD math: RMDs begin at 75 (SECURE 2.0). A $1.9 million balance growing at 5% for 17 years would be roughly $4.35 million; the first RMD divisor at 75 is about 24.6, implying roughly $177,000 in year-one RMD - likely pushing her into higher brackets and possibly IRMAA. Reducing the traditional balance now lowers that trajectory.
- Why not all at once: a full conversion would push her far above the 24% bracket into 32%–37%, plus potential NIIT and IRMAA, and would consume the taxable account to pay the tax. Bracket-filling over the 12 years from 58 to 70 - while her income is low and before Social Security starts - is the efficient window.
- Pay tax from taxable assets: paying conversion tax from outside the IRA maximizes the benefit, but she should preserve the taxable account for pre-59½ spending and harvest gains at favorable rates.
- Roth five-year rules: she has a Roth open 12 years, so the five-year clock for qualified distributions is satisfied; converted amounts have their own five-year clock for penalty-free access to converted principal, which matters if she needs funds before 59½.
- Legacy and flexibility: Roth assets have no lifetime RMDs and are favorable for heirs, but do not let that override bracket discipline.
Recommend annual conversion modeling with a target bracket and IRMAA threshold, revisited each fall.