The zero-tax conversion window

A 65-year-old couple can convert $47,500 to a Roth with zero federal tax in 2026 by filling their standard deduction and age-based deductions. This rare low-income window happens between retirement and required distributions.

How the math works for 2026

The standard deduction for married couples is $32,200, plus additional amounts for both spouses age 65 and the new senior deduction. Combined, this creates a $47,500 deductible layer that can be filled with a conversion at zero tax.

The calculation advisors skip

Most conversion advice ignores the critical question: what will their required minimum distribution actually be? At $380,000, this couple's first RMD at age 75 under SECURE 2.0 rules won't push them into higher tax brackets.

“If the required distribution arrives inside the low brackets anyway, converting now to avoid a bracket that will never appear saves very little.”

The RMD plus Social Security test

With a $380,000 IRA and plausible Social Security benefits, this couple's household income stays well below the 22% tax bracket threshold of $100,800 in early distribution years. Converting to avoid a bracket they'll never reach saves nothing.

Medicare premiums are the hidden cost

A 2026 conversion affects 2028 Medicare premiums through income-related monthly adjustment amounts. The first IRMAA tier begins at modified adjusted gross income above $218,000, and a conversion can push more Social Security into the taxable share.

Conversion is permanent and costly

Recharacterization was eliminated in 2017, so conversion cannot be undone. Paying taxes from outside the IRA is essential, and several states tax conversions fully with no offsetting deduction.

When converting actually makes sense

Converting pays off if one spouse will likely outlive the other by many years and face higher single-filer brackets, or if non-spouse heirs will inherit and must empty the account within 10 years during their peak earning years.

The verdict for this couple

For a healthy 65-year-old couple with $380,000, no other income sources, and no non-spouse heirs, converting is motion without payoff. Their projected RMD plus Social Security stays in the 12% bracket.

“For a healthy 65-year-old couple with $380,000, no meaningful other income sources, and no plan to leave the account to non-spouse heirs, filling deductions with a conversion is motion without payoff.”

Run this one number first

Before converting, add your projected first-year required distribution to your expected Social Security income. If that total stays comfortably below $100,800, the conversion is solving a problem that won't exist.