U.S. — Higher income thresholds apply to subsequent brackets. The 22% federal income tax bracket for joint filers tops at $211,400 for tax year 2026, and the 22% federal income tax bracket for single filers tops at $105,700 for tax year 2026. According to reports from taxfoundation.org, the 32% federal income tax bracket for married couples filing jointly begins above $403,550 in 2026.

These adjustments intersect with rules governing Roth IRAs. A Roth IRA has no required minimum distributions for the original owner. Converting a traditional IRA to a Roth IRA during one's 60s eliminates required minimum distributions at age 73. The SECURE 2.0 Act set the required minimum distribution start age to 73 for individuals born between 1951 and 1959.

Each Roth conversion starts a separate five-year clock before earnings can be withdrawn tax-free. While Internal Revenue Code §408A states that a conversion of a traditional IRA to a Roth IRA is not included in gross income in the year of the conversion, the transaction affects other financial calculations.

Roth conversions increase modified adjusted gross income, which Medicare uses with a two-year lookback to determine IRMAA surcharges. The 2026 Medicare IRMAA brackets for joint filers begin above $218,000 in modified adjusted gross income. The top Medicare IRMAA surcharge for joint filers applies at $750,000 in modified adjusted gross income.

Conversion income increases the taxable portion of Social Security benefits and can push provisional income past the 85% threshold. Internal Revenue Code Social Security taxation rules state that the amount of social security benefits that are subject to tax is based on the taxpayer's provisional income. The SEC legally requires fiduciaries to put client interests first.

How Sources Differ

Sources differ on specific figures for married couples filing jointly. IRS Revenue Procedure 2025-32 states that the standard deduction for married couples filing jointly is $32,200 for tax year 2026. In contrast, taxfoundation.org reports that the 32% federal income tax bracket for married couples filing jointly begins above $403,550 in 2026.

Why It Matters

The inflation adjustments define the income ranges where taxpayers face different marginal rates, directly influencing the cost of Roth conversions. Because Roth conversions increase modified adjusted gross income, they trigger Medicare Income-Related Monthly Adjustment Amount surcharges based on a two-year lookback period. The gap between the 12% bracket ceiling of $100,800 and the top IRMAA threshold of $750,000 represents a 644% increase for joint filers.

Taxpayers must also consider how conversion income affects Social Security taxation. Conversion income increases the taxable portion of Social Security benefits and can push provisional income past the 85% threshold. Each Roth conversion starts a separate five-year clock before earnings can be withdrawn tax-free, adding complexity to withdrawal planning for those converting in their 60s to eliminate required minimum distributions at age 73.