Required Minimum Distribution Tax Treatment

A required minimum distribution is money you must withdraw from a traditional IRA or 401(k) after age 73, and the IRS taxes it as ordinary income. Even if you do not need the money, the withdrawal inflates your income for the year—potentially pushing you into a higher tax bracket and triggering taxation of Social Security benefits that would otherwise be free.

Why RMDs are taxed as ordinary income

When you contributed to a traditional IRA or 401(k), those contributions reduced your taxable income. The IRS deferred tax, not eliminated it. A required minimum distribution is the IRS calling in that debt.

RMDs are treated identically to ordinary withdrawals: the full amount is added to your adjusted gross income. If you are in the 24% federal bracket, a $50,000 RMD costs you $12,000 in federal tax. State income tax may apply on top. Unlike qualified dividend income or long-term capital gains, RMDs do not get preferential rates—they are taxed at the same rates as wages or ordinary income.

This creates a tax liability whether or not you need the money. A retiree living on Social Security and investment returns may face a surprise RMD that inflates their income and pushes them into a higher bracket.

How RMDs push retirees into higher brackets

Suppose a retiree has $500,000 in a traditional IRA and is age 75. Using the IRS life-expectancy factor for age 75 (roughly 22.9), the annual RMD is approximately $21,850.

If the retiree’s other income is $60,000 (Social Security and pension), the RMD pushes total adjusted gross income to $81,850. The RMD alone may push income across a bracket threshold, raising the marginal rate from 12% to 22% (for single filers in 2024, that threshold is around $47,150). The last dollar of the RMD may be taxed at the higher rate.

Even worse: when income crosses into the next bracket, not only RMD dollars are taxed at the new rate—all income in that higher bracket is. For a single filer, the first $47,150 is taxed at 12%, and the excess at 22%. Adding a $21,850 RMD means roughly $21,850 is taxed at 22%.

The marginal rate can be substantially higher for high-income retirees: 32%, 35%, or even 37%.

The Social Security taxation trap

Here is where RMDs create the biggest surprise: they count toward your “combined income” threshold for Social Security taxation.

Combined income = half your Social Security benefits + all other income, including RMDs.

For a single filer:

• Combined income below $25,000: no Social Security is taxable.
• $25,000 to $34,000: up to 50% of benefits are taxable.
• Above $34,000: up to 85% of benefits are taxable.

Married filers have higher thresholds ($32,000 and $44,000, respectively).

If a retiree receives $30,000 in Social Security and has an RMD of $25,000, combined income is $30,000 + $25,000 + (0.5 × $30,000) = $70,000. This exceeds the $34,000 threshold, triggering taxation of up to 85% of the Social Security benefit. The RMD alone created $36,000 in additional income threshold, turning a previously tax-free benefit into a partially taxable one.

The math is harsh: a $25,000 RMD can cause $25,000 of Social Security to become taxable, effectively taxing Social Security at the same marginal rate as the RMD itself. For a retiree in the 22% bracket, that is an implicit combined rate of 44% on RMDs once Social Security taxation is included.

Calculating your RMD

The IRS publishes life-expectancy factors each year. For a traditional IRA, you divide the account balance as of December 31 of the prior year by the factor for your age.

If your balance on December 31 of Year 1 is $400,000 and you are age 73, the factor is 26.5 (rounded), so your RMD is $400,000 ÷ 26.5 = $15,094.

401(k) RMDs use the same life-expectancy tables (the Uniform Lifetime Table for most people), with one exception: if your spouse is the sole beneficiary and is more than 10 years younger, you can use an even longer life expectancy, deferring RMDs further.

The calculation must be completed by December 31 of each year. Some 401(k) plans and IRA custodians calculate RMDs automatically; others require you to request the calculation.

The penalty for missing an RMD

If you do not withdraw at least your full RMD by December 31, the IRS imposes a penalty equal to 25% of the shortfall (reduced to 10% under SECURE 2.0 for certain relief scenarios; penalties for subsequent failures are 10%).

If your RMD is $20,000 and you withdraw only $15,000, the shortfall is $5,000, and the penalty is $1,250 (at the full 25% rate). This is in addition to the income tax you owe on the $15,000 you did withdraw. You must also withdraw the shortfall later and pay tax on it.

The penalty does not apply if you have a valid excuse (such as certain disaster relief), and the IRS has discretion to waive it, but do not rely on that. The safe path is to withdraw the full RMD before year-end.

Strategies to manage RMD tax impact

Some retirees use qualified charitable distributions: directly transferring up to $100,000 per year from an IRA to a charity. The distribution does not count as taxable income, yet satisfies the RMD. This is available only to IRA holders age 70½ and older.

Others accelerate Roth conversions before RMDs begin, moving assets into a tax-free account where RMDs do not apply. A Roth conversion triggers ordinary income tax in the conversion year, but thereafter, the converted balance grows and withdraws tax-free, avoiding both RMD taxation and Social Security taxation triggers.

Delaying Social Security receipt can also help: lower benefit amounts mean a lower combined income threshold, reducing the RMD’s impact on Social Security taxation.

See also