RMDs and IRMAA: when required distributions push you over

How RMDs are calculated

Once you reach your required beginning age, the IRS requires you to withdraw a minimum amount from your tax-deferred retirement accounts each year. Under current law that age is 73 for people born from 1951 through 1959 and 75 for people born in 1960 or later. Roth IRAs have no lifetime RMDs.

The amount is your account balance on December 31 of the previous year divided by a life expectancy factor from the IRS Uniform Lifetime Table in Publication 590-B (a different table applies if your spouse is more than ten years younger and is your sole beneficiary). The factor shrinks as you age, so the share you must take grows: about 3.8% at 73, 4.1% at 75, 5% at 80 and 6.3% at 85.

A worked example

James is single and has $1,200,000 in a traditional IRA. His pension, Social Security and other income come to $70,000 of MAGI before any RMD. On its own, that is $39,000 below the first IRMAA limit. Here is what his RMD does at different ages, holding the balance at $1.2 million to keep the comparison simple:

At 75, the RMD of $48,780 lifts James to $118,780, which is $9,780 into tier one. He pays $1,148.40 a year more than on the standard premium. By 80 he still has $7,594 of room before tier two, and by 85 he has crossed it. In real life his balance would also change with markets and withdrawals, but the direction is the same: RMDs climb faster than most people expect.

Five ways to soften the RMD effect

1. Convert before RMDs begin

The years between retirement and your required beginning age are often your lowest-income years. Converting part of the IRA to a Roth then, within your headroom, shrinks the balance that RMDs are calculated on. After 63, size each conversion with the Roth headroom finder.

2. Use qualified charitable distributions

From age 70½ you can send money directly from an IRA to a charity. That qualified charitable distribution counts toward your RMD but is left out of adjusted gross income, so it lowers MAGI dollar for dollar. If James gives $10,000 a year to his church, sending it as a QCD would keep $10,000 out of his MAGI. See using QCDs to lower IRMAA.

3. Watch the first-year double RMD

You may delay your first RMD until April 1 of the following year, but then you take two RMDs in that second year. Two distributions in one year can push you over a cliff that one would not. Taking the first one in the year you reach the required age often avoids the spike.

4. Hold growth investments in the Roth

The faster the traditional IRA grows, the larger future RMDs become. Some retirees keep bonds in the traditional IRA and stocks in the Roth so the taxable balance grows more slowly. This is an asset-location choice to discuss with an adviser.

5. Keep other income flexible

Large capital gains or a conversion in the same year as a big RMD can stack up. Spreading them across years keeps each year inside its tier.

Still working past 73?

If you still work for the employer that sponsors your 401(k) and do not own more than 5% of the company, you can usually delay RMDs from that plan until you retire. IRAs do not get this exception. Your salary still counts toward MAGI, so working years often carry IRMAA anyway; the first RMD year after retiring can then come as an extra jump.

RMDs for surviving spouses

When one spouse dies, the survivor can usually treat the inherited IRA as their own, and the combined balance then drives a single, larger RMD. At the same time, from the year after the death the survivor files as single and faces the individual IRMAA limits, half of the joint ones. That combination, a bigger RMD on a smaller limit, is a common route into IRMAA in a person's 80s. Converting part of the IRA while both spouses are alive and filing jointly spreads the tax over years when the wider joint tiers apply.

Frequently asked questions

Sources

• IRS Publication 590-B: Uniform Lifetime Table and RMD rules
• IRS: Required minimum distributions FAQs
• CMS: 2026 Medicare Parts B premiums and deductibles

Related guides

• Using QCDs to lower IRMAA
• Roth conversions and IRMAA
• How to lower IRMAA: 10 strategies