Updated July 29, 2026. Quick answer: The statute doubles the single thresholds for joint filers at every tier except the top one, where it uses 150% instead. So unlike the income tax brackets — which are exactly half and actually favour the single filer at the top — IRMAA has genuine compression, and it lands hardest on the highest-income survivors.
The carve-out, in the statute’s own terms
42 U.S.C. §1395r(i) applies “dollar amounts which are twice the dollar amounts otherwise applicable” for joint filers — except that for the last row of the table it applies “dollar amounts which are 150 percent.”
| Tier | Joint threshold relative to single |
|---|---|
| All tiers except the top | 200% |
| Top tier | 150% |
And a survivor whose income does not change at all can still cross into a higher tier, at every tier, purely because the applicable thresholds halve when the filing status changes. That is a real increase in Medicare premiums caused by a death rather than by any change in the survivor’s circumstances.
Two indexing regimes in one table
Most thresholds adjust annually by a consumer price measure. The top-tier figures are expressly excluded from that adjustment until a later statutory date, with a separate mechanism after it. So the top tier catches more people every year by drift alone, in addition to the compression.
Relief exists but is narrower than it sounds — the death of a spouse is a qualifying life-changing event, and that still may not help.
Every dollar figure in this area is indexed and none is quoted here. The rate-schedule thresholds, the standard deduction, the estate exclusion and the IRMAA tiers all move annually, and two of them move on their own separate schedules. Take current figures from the IRS or the Social Security Administration for the year in question.
Sources
IRC §1(j)(2)(A) and (j)(2)(C); §2(a) and §2(b); §6013(a); §63(c)(2), (c)(7) and (f)(3); §121(a), (b)(2)(A) and (b)(4); §72(t)(2)(A); Treas. Reg. §1.408-8(c); §408(d)(3)(C); §2010(c)(5)(A); Rev. Proc. 2022-32; 42 U.S.C. §402(k)(3)(A) and §1395r(i); 20 C.F.R. §418.1201 and §418.1205. All read July 2026.
This states what the cited authority says. It is not tax advice, and retirement-plan design turns on facts about your business and your other entities that no page can see. Every dollar limit referenced here is indexed and changes annually.