Most retirees assume their Medicare premiums are fixed—but that’s not the case. What many don’t realize is that Medicare Part B and Part D premiums are income-tested, and the income used to calculate those premiums comes from your tax return two years prior. That lag can create costly surprises if you’re not planning ahead.
Consider the case of “Linda,” a 68-year-old retiree. In 2024, she decided to sell the business she and her late spouse had owned for many years. The transaction generated a large long-term capital gain. At the time, Linda was understandably pleased with the proceeds, after all, it represented years of investment and appreciation. What she didn’t anticipate was how that one financial decision would ripple into her future healthcare costs.
Fast forward to 2026. Linda received a notice from Social Security outlining her updated Medicare premiums. Her monthly Medicare Part B premium had increased by over $400! Even more frustrating, those elevated premiums won’t immediately drop. They’ll remain in place until her reported income falls back below certain thresholds on a future tax return.
This situation is driven by what’s known as Income-Related Monthly Adjustment Amounts, or IRMAA. These surcharges apply when your modified adjusted gross income exceeds specific limits. For 2026, the first IRMAA tier begins at $109,000 for single filers and $218,000 for married couples filing jointly. Once you cross that threshold, premiums don’t just inch up, they can increase significantly, in some cases by as much as 240% per person.
What makes this particularly challenging is that these thresholds haven’t kept pace with inflation in a meaningful way. As a result, more middle-income retirees are being pulled into higher premium brackets each year, not because they’re “wealthy,” but because of one-time income events like asset sales or large withdrawals.
The encouraging news is that many of these premium spikes are preventable. With proactive planning, retirees can often manage their income levels to avoid crossing IRMAA thresholds. Strategies such as phased Roth conversions, coordinated charitable giving, tax-efficient withdrawal sequencing, and thoughtful timing of Social Security benefits can all play a role in keeping income within target ranges.
In Linda’s case, she could’ve appealed the premium increase due to a qualifying life-changing event—the loss of her spouse. However, a more effective approach would have been planning the property sale in advance. Techniques like spreading the gain over multiple years through an installment sale, or incorporating certain charitable strategies, could have significantly reduced the income spike and the resulting Medicare surcharges.
If you’re approaching retirement, or already there, and anticipating a major financial event, it’s worth taking a closer look at how it could impact your Medicare premiums. Large IRA withdrawals, real estate sales, stock option exercises, and even bonuses can all trigger higher costs if not carefully managed.
A bit of forward planning can go a long way. In many cases, just a few hours of analysis and coordination can prevent thousands of dollars in unnecessary Medicare expenses.
