Retirees Brace for a $1.2M 401(k) Tax Shock at Age 73 Today

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On May 10, 2026, retirees holding large traditional 401(k) balances are being warned that required withdrawals at 73 could sharply raise taxes and Medicare costs.

Retirement Tax Bomb Nears for $1.2M 401(k) Savers

A retiree with $1.2 million in a traditional 401(k) could face a first required minimum distribution near $52,000 at age 73 after modest portfolio growth. Combined with roughly $40,800 in annual Social Security income, taxable income may climb toward $93,000, creating a federal tax bill between $11,000 and $13,000.

Medicare Costs Could Rise Faster Than Expected

The warning deepens because Medicare IRMAA surcharges begin once modified adjusted gross income crosses $109,000 for single filers. Financial planners are increasingly highlighting Roth conversions between ages 70 and 72, typically ranging from $135,000 to $150,000 annually, to reduce future taxable withdrawals. “The clock typically ticks louder after 73,” retirement advisers warn as shrinking RMD divisors increase annual withdrawals.