She turned 73 this year, and her IRA custodian’s letter arrived with weight. Her first required minimum distribution (RMD) is due, and weeks of back-of-the-envelope math keep showing the same result: forced withdrawals will drain her traditional IRA, and the extra income will drag more of her Social Security into taxable territory. Online forum threads from new retirees in their first RMD year read identically, with a recurring worry that the IRS has rigged the rules to empty the account.
The reassurance is hiding in plain sight, written into the IRS Uniform Lifetime Table itself. The data is built on an assumption that makes the required withdrawal smaller than most people expect, and that single design choice softens the tax hit on her Social Security.
The Divisor Assumes a Younger Beneficiary
The Uniform Lifetime Table calculates her required withdrawal as if her IRA had a beneficiary exactly 10 years younger than she is. There is no such person required. The IRS bakes that assumption into the math, which stretches the schedule out. At age 73, the divisor is roughly 26.5, which works out to a required withdrawal of about 3.8% of her December 31 balance.
Compare that with the Social Security Administration’s (SSA’s) actuarial tables, which put a 73-year-old’s remaining life expectancy in the 13 to 15 year range. If the IRS used her real life expectancy, the required percentage would be nearly double. Instead, the rule is structurally generous. The account is meant to last.
The percentage climbs with age. By 80, the required withdrawal rises to roughly 5% of the balance, and by 85 it is closer to 6%. Even at those ages, the math is gentler than her actual lifetime would justify. A balance earning a reasonable return through her 70s can still grow in dollar terms, even as she takes the required amount each year.
Why a Smaller Withdrawal Means Less Tax on Her Benefit
Social Security taxation works on a sliding scale tied to combined income, which is roughly adjusted gross income (AGI) plus any tax-exempt interest plus half of her Social Security. Once combined income crosses certain thresholds, a portion of her benefit becomes taxable, with up to 85% of the benefit potentially subject to ordinary income tax. That 85% refers to the share of the benefit added to taxable income, which is then taxed at her ordinary income rate.
Because her RMD is smaller than feared, the dollar amount layered on top of her Social Security is smaller too. That keeps a larger slice of her benefit out of the taxable column. The same logic applies to Medicare. Lower forced income reduces the chance of crossing into a higher Income-Related Monthly Adjustment Amount (IRMAA) tier, which would raise her Part B and Part D premiums two years later.
The RMD itself is fully taxable as ordinary income, and it can still pull some additional Social Security into the taxable zone. The divisor’s design caps how aggressive that effect can get in any single year.
The COLA Effect
The 2026 cost-of-living adjustment (COLA) of 2.8% raised her gross Social Security income before any of this tax calculation happens. That bump matters because the income thresholds for taxing Social Security are not indexed to inflation. Every COLA pushes more dollars of benefit into the taxable zone over time, regardless of what her IRA is doing.
A qualified charitable distribution lets her send part of her RMD directly from the IRA to a qualifying charity, and the transferred amount never shows up in her adjusted gross income. For a retiree who already gives to her church or a cause she cares about, that move can shrink the tax torpedo without requiring her to give more than she already planned to.
What Actually Matters
Two points are worth holding onto:
- The IRS designed the table to preserve the account. The Uniform Lifetime Table is calibrated to leave most retirees with a balance well into their 90s. The first-year required percentage is small enough that her IRA can keep growing if her investments cooperate.
- The tax effect on her Social Security is bounded by the size of the RMD. Because the required amount is modest, the share of her benefit pulled into taxable territory is modest too. Up to 85% can be taxed in extreme cases, but most retirees at her income level land well below that ceiling.
The mistake hardest to undo is panic-selling assets inside the IRA or withdrawing far more than required because the rules felt threatening. RMD age stays at 73 for those born between 1951 and 1959, and 75 for anyone born in 1960 or later, so the timing rules will vary for friends and siblings who ask. A short conversation with a tax preparer who has seen this scenario before can settle the rest.
Contact [email protected] for any questions or corrections.
Top Gaining Stocks
Top Losing Stocks