Skip to navigationSkip to main contentSkip to right columnADVERTISEMENTCarl SullivanMon, June 8, 2026 at 12:21 PM GMT+2 6 min readQuick ReadCrossing the $109,000 MAGI threshold by even $1 triggers roughly $1,150 in extra annual Medicare Part B and Part D premiums.CMS calculates IRMAA using income from two years prior, closing the planning window before most retirees realize they've crossed the line.Bracket-filling Roth conversions before Medicare enrollment at 65 reduce future RMDs and keep MAGI below the $109,000 IRMAA cliff.Many financial professionals are salespeople paid on what they push, not whether you end up wealthier. A fiduciary is the opposite. The SEC legally requires them to put your interests first. Advisor.com's free matching tool pairs you with vetted fiduciaries from firms like Vanguard, Empower, and Edelman — in under three minutes. See who you match with today.A retired math teacher in her mid-60s with a seven-figure 403(b) did the responsible thing. She kept her withdrawals modest, lived below her means, and assumed her income was predictable. Then an unexpected bill arrived from Medicare.Let's assume our 64-year-old retired from a public school system with a $48,000 state pension and $1.1 million in a 403(b). She mapped out a conservative drawdown of $36,000 per year from the 403(b), bringing her ordinary income before Social Security to roughly $84,000. Comfortable, well under the top brackets, and seemingly nowhere near any income cliffs.Then she enrolled in Medicare and discovered an Income-Related Monthly Adjustment Amount (IRMAA) surcharge attached to her Part B and Part D premiums. The trigger was modified adjusted gross income (MAGI) from two years earlier, when a Roth conversion, a strong taxable account distribution, or the addition of Social Security benefits pushed her across a single threshold she never tracked.On Suze Orman's podcast, a 61-year-old retired educator recently asked the same underlying question: When and how to move money from a 403(b) to a Roth without creating a tax problem. Orman's answer leaned heavily on whether the pension alone covered living expenses, because "money that you withdraw from a traditional IRA counts towards income to calculate if you're going to pay tax on your Social Security or not. That is money that is used to calculate what your Medicare B premiums are going to be, and they will be higher because of that."The federal tax code is gradual. Under the 2026 brackets, 22% kicks in at $50,400 of taxable income for single filers, and 24% does not start until $105,700. One extra dollar of income costs a few cents of marginal tax.Terms and Privacy PolicyPrivacy & Cookie SettingsMore Info