A 65-Year-Old With $1.3M in a 401(k) Avoids the IRMAA Trap With This $50,000 Withdrawal Strategy

A 65-year-old with $1.3 million in a traditional 401(k) just enrolled in Medicare, isn’t yet drawing Social Security, and wants $50,000 a year to live on. That is a 3.8% withdrawal rate, well inside any reasonable sustainability range. The spreadsheet math works fine. The Medicare premium bill two years from now is the real constraint.

This is the window between 65 and 73 that most retirees underuse. Required minimum distributions don’t start until age 73. Social Security can wait until 70. For eight years, this retiree controls almost every dollar of taxable income that lands on a 1040. What gets pulled out of the 401(k) in 2026 sets the Medicare premium for 2028, because IRMAA uses a two-year lookback on modified adjusted gross income.

Why $50,000 Hits the Tax Sweet Spot

Pulling $50,000 from a traditional 401(k) generates $50,000 of ordinary income. For a single filer who is 65 or older in 2026, the standard deduction plus the new senior bonus deduction stacks to roughly $23,750. Taxable income lands near $26,000, putting the federal bill in the low single-digit thousands and keeping the household squarely in the 12% bracket.

More importantly, $50,000 of MAGI sits $59,000 below the first IRMAA tier for single filers, which kicks in at $109,000 of MAGI. A married couple filing jointly has even more room: the first surcharge tier doesn’t start until $218,000, and the senior standard deduction climbs to roughly $46,700 when both spouses are 65 or older.

The Surcharge Most Retirees Don’t See Coming

Cross the first IRMAA threshold by a single dollar in 2026 and the 2028 Medicare bill jumps. The standard Part B premium for 2026 is $202.90 per month. Tier 1 adds $81.20 to Part B and another $14.50 to Part D, or about $1,148 per person, per year. For a couple, that is roughly $2,297. Tier 2 is closer to $2,886 per person, and the top tier reaches $8,279.

The cruelty of the cliff is that it isn’t graduated. One dollar of MAGI over $109,000 triggers the full Tier 1 surcharge. That makes IRMAA a marginal-rate event masquerading as a flat fee. A retiree who pushes withdrawals from $50,000 to $110,000 to fund a kitchen remodel adds about $1,150 in Medicare premiums to whatever federal tax the extra $60,000 already generated.

Using the Gap Years to Lower Future RMDs

Here is where the $50,000 plan becomes a tax strategy rather than a withdrawal strategy. A single filer can convert another $59,000 from the traditional 401(k) to a Roth IRA in 2026 and still stop just under the IRMAA threshold. A couple has even more headroom, with roughly $168,000 of conversion space before the first surcharge tier.

The arithmetic is straightforward. With the 10-year Treasury near 4.6% and inflation still running hot relative to the past year, a balanced 401(k) compounding at 6% will likely double by age 73. A $1.3 million balance grown to $2 million produces a first-year RMD near $75,000. Conversions done now at 12% spare the saver from withdrawals taxed at 22% or 24% later, and they shrink the RMD that pushes future MAGI through every IRMAA tier in sequence.

Three Moves Worth Making This Year

1. Anchor the plan to a MAGI ceiling. Keep the combined 401(k) draw plus any Roth conversion under $109,000 single or $218,000 MFJ for 2026. Stopping $2,000 to $5,000 short of the line preserves a buffer for surprise capital gains or interest income.
2. Treat the gap years as conversion years. Between 65 and 73, every dollar converted at 12% is a dollar that won’t be forced out at 22% inside an RMD plus Social Security plus IRMAA stack. SECURE 2.0 made high-earner catch-up contributions mandatorily Roth, signaling the direction tax policy is heading.
3. File Form SSA-44 if 2024 income was high. A retiree who left a $200,000 job in 2025 may be paying IRMAA in 2026 based on working-year MAGI. The life-changing-event form can wipe the surcharge retroactively for the retirement year.

The $50,000 question was never about whether $1.3 million can support the lifestyle. The Fed funds rate sits at 3.75% and bond yields are doing real work again. The question is whether the next eight years get used to flatten the tax curve or to feed it.