Medicare IRMAA | Roth Conversion & Medicare | Medicare Planning For Business Owners

For business owners and executives, Medicare is also a tax decision. Your income, your exit timing, and even a Roth conversion can change what you pay.

Ask a successful business owner about retirement planning, and you'll likely hear about succession, investments, and taxes. Medicare rarely makes the list until 65 is close. Yet the income you report in your early 60s can quietly set your Medicare premiums for years.

GBQ Partners and The Siekmann Company explored that connection in Medicare Made Simple: Understanding Your Coverage Options. Andrew Gordon, a business development strategist with MFS Investment Management, led the discussion. 

Why Is Medicare A Tax Planning Issue?

Medicare Part B and Part D premiums are tied to your modified adjusted gross income (MAGI) from two years earlier. In 2026, the standard Part B premium is $202.90 per month. Higher earners pay an income-related monthly adjustment amount (IRMAA) on top of it. Each person pays separately, so a married couple faces the surcharge twice.

The brackets work like cliffs. Gordon pointed out that landing even a dollar over a threshold triggers the higher premium for the full year.

Can A Roth Conversion Raise Your Medicare Premiums?

It can. Gordon said one of the most common traps he sees is a large Roth conversion completed in someone's early 60s, before Medicare starts, without considering the look-back. Capital gains have the same effect.

That doesn't make conversions a bad idea. In some years it may make sense to accept a higher premium in exchange for lower taxes later. The point is to model the Medicare cost alongside the tax savings, ideally a few years before 65.

What If Your Income Drops After You Step Away?

Many owners earn the most in the years right before they retire, then see income fall sharply. Form SSA-44 lets you ask the Social Security Administration (SSA) to base IRMAA on more recent income after a qualifying life-changing event, such as work stoppage. Gordon called it one of Medicare's best-kept secrets (it's sitting right on the SSA website). The form lists specific qualifying events, so confirm which apply to you before counting on it.

Which Coverage Path Fits Your Lifestyle?

Coverage choices matter for high-net-worth households, too:

  • Medigap pays costs such as the Part A deductible and Part B's 20% coinsurance. It trades higher premiums for predictable costs. Buy it during your six-month Medigap open enrollment period, when insurers can't use medical underwriting.
  • Medicare Advantage often bundles drug, dental, and vision benefits, but networks tend to be regional. If you split the year between Ohio and Florida, Gordon suggested confirming coverage in both places.
  • Still working past 65 with a health savings account (HSA)? Part A can be backdated up to six months when you enroll later, so HSA contributions generally need to stop well before you apply.

What You'll Learn In The Full Webinar

  • How the two-year income look-back affects Part B and Part D premiums.
  • Why Roth conversion timing should account for Medicare costs.
  • How Form SSA-44 may reduce IRMAA after retirement.
  • How Medigap and Medicare Advantage compare for people who travel.
  • When each Medicare enrollment window applies to you.

Watch The Webinar


Bring Medicare Into Your Retirement Plan

Medicare costs belong in the same conversation as your exit strategy, Roth conversions, and investment income. GBQ's Private Client and Wealth Management teams can help you weigh those decisions together. The Siekmann Company, a strategic partner of GBQ, can help with the Medicare and benefits side.

Empowering growth is only a conversation away. Talk to an expert about how Medicare fits your retirement plan.


Frequently Asked Questions

What income is used to calculate IRMAA?

IRMAA uses your MAGI from the tax return filed two years earlier, so 2026 premiums are based on 2024 income. For this purpose, MAGI is your adjusted gross income plus tax-exempt interest. Roth conversions, capital gains, and other one-time income can push you into a higher bracket.

Do Medicare premiums apply per person or per household?

Per person. Many employer plans offer family coverage, but each spouse enrolls in Medicare individually and pays an individual premium. If your joint income exceeds an IRMAA threshold, both spouses typically pay the surcharge.

Can I appeal a high Medicare premium after I retire?

Yes, if a qualifying life-changing event such as work stoppage lowered your income. You can request a new IRMAA determination by filing Form  SSA-44 with supporting documentation. The SSA may then use your more recent, lower income to set your premium.