A growing number of affluent investors in their 60s and early 70s are executing a specific retirement tax strategy: converting substantial portions of their traditional 401(k) accounts into Roth IRAs before required minimum distributions (RMDs) begin at age 73. This timing is not coincidental. The window between retirement and the start of mandatory withdrawals offers a unique opportunity to reshape the tax profile of retirement assets, and those with significant savings are taking advantage of it.

Understanding Required Minimum Distributions

According to the Internal Revenue Service, RMDs are mandatory annual withdrawals that must begin from traditional retirement accounts once an account holder reaches age 73 (Internal Revenue Service, 2026). The requirement exists because traditional 401(k) and IRA contributions were made with pre-tax dollars, and the government eventually requires taxes to be paid on that deferred income.

The withdrawal amounts are calculated based on account balance and life expectancy, and they increase each year. For someone with a $2 million traditional 401(k) at age 73, the first-year RMD would be approximately $75,000, which must be reported as ordinary income. These distributions cannot be avoided or delayed without incurring steep penalties (50% of the amount that should have been withdrawn).

The Roth Conversion Mechanism

A Roth conversion involves moving funds from a traditional 401(k) or traditional IRA into a Roth IRA. The converted amount is treated as taxable income in the year of conversion, meaning the account holder pays income tax on the full amount moved. However, once inside the Roth IRA, the money grows tax-free, and qualified withdrawals in retirement are completely tax-free.

Unlike traditional retirement accounts, Roth IRAs are not subject to RMDs during the account holder’s lifetime. As covered in Principles of Finance, this fundamental difference in tax treatment creates strategic planning opportunities (OpenStax, 2022).

Why the Window Between 60 and 73 Matters

The years between early retirement (often age 60 to 65) and age 73 represent what tax planners call the “conversion window.” During this period, many affluent individuals have stopped working but have not yet triggered RMDs. This creates a temporary dip in taxable income, potentially dropping them into lower tax brackets than they occupied during peak earning years or will face once RMDs begin.

By converting portions of a traditional 401(k) to a Roth IRA during these lower-income years, investors can pay taxes on the conversion at potentially reduced rates. The strategy becomes particularly attractive when current tax rates are historically low or when investors anticipate higher tax rates in the future, whether from legislative changes or from their own increased income once RMDs begin.

The Tax Calculation

Consider an investor who retires at 62 with a $3 million traditional 401(k). Without earned income, this person might temporarily fall into the 22% or 24% federal tax bracket. By converting $200,000 per year for several years before age 73, they pay tax at these relatively modest rates.

The alternative scenario: waiting until RMDs force withdrawals. At age 73, RMDs combined with Social Security benefits and any pension income could push total taxable income well into the 32% or even 35% bracket. The tax savings from converting during the lower-bracket years can be substantial over a retirement that may last 20 or 30 years.

Read also: The Roth Conversion Strategy Affluent Investors Over 60 Are Using to Empty Their 401(k)s

Estate Planning Advantages

Beyond personal tax benefits, Roth conversions offer significant advantages for wealth transfer. Roth IRAs pass to heirs tax-free (though the SECURE Act of 2019 requires most non-spouse beneficiaries to withdraw the full account within 10 years). For affluent families concerned about leaving tax-efficient inheritances, paying the conversion tax now removes a future tax burden from their children or grandchildren.

Traditional 401(k) and IRA assets, by contrast, saddle heirs with ordinary income tax on every dollar withdrawn. For beneficiaries in high tax brackets, this can claim 30% to 40% of the inherited value in federal and state taxes.

Who Benefits Most From This Strategy

This strategy works best for investors who meet several criteria. First, they must have sufficient assets outside of retirement accounts to pay the conversion taxes without dipping into the retirement funds themselves. Second, they should have at least 10 to 15 years for the Roth assets to grow and recover the tax cost of conversion. Third, they expect to be in a higher tax bracket during RMDs than during the conversion years.

The strategy is particularly powerful for those who do not need their retirement accounts for living expenses and plan to leave substantial assets to heirs. These investors are essentially pre-paying their estate’s tax bill at today’s rates.

Important Considerations

Roth conversions are irrevocable decisions that trigger immediate tax liability. Large conversions can push taxpayers into higher brackets, potentially affecting Medicare premiums through Income-Related Monthly Adjustment Amounts (IRMAA). Converting too much in a single year can backfire if it causes a bigger tax hit than spreading conversions over multiple years.

The strategy also assumes no urgent need for the converted funds, as Roth IRA earnings can only be withdrawn tax-free and penalty-free after age 59.5 and after the account has been open for at least five years.

Conclusion

The surge in Roth conversions among affluent retirees reflects sophisticated tax planning rather than panic. By understanding the mechanics of RMDs and strategically timing conversions during lower-income years, investors can reduce lifetime tax burdens and leave more tax-efficient inheritances. As with any significant financial decision, this strategy works best when tailored to individual circumstances and executed as part of a comprehensive retirement plan.

This article provides general educational information and is not personalized financial or tax advice. Tax laws are complex and subject to change. Consult a certified public accountant or qualified tax advisor before executing Roth conversions or other retirement account strategies. Individual results will vary based on account balances, tax brackets, state tax laws, and personal financial situations.