A retired teacher in Ohio pulling $22,000 a year from her pension and $1,800 a month in Social Security would not strike most people as wealthy. But under federal tax math written more than four decades ago, she likely qualifies for taxation on her benefits. The income thresholds that trigger federal tax on Social Security were set in 1983 and 1984, and Congress never built in a single mechanism to adjust them. Not for inflation. Not for wage growth. Not for anything. In 2026, those same frozen dollar figures keep dragging more retirees into a tax many never saw coming.
How the thresholds work and why they haven’t moved
Before 1984, Social Security benefits were entirely exempt from federal income tax. The 1983 Social Security Amendments changed that by creating a formula called “combined income”: adjusted gross income, plus nontaxable interest (such as municipal bond earnings), plus half of Social Security benefits. If that total exceeded $25,000 for a single filer or $32,000 for a married couple filing jointly, up to 50% of benefits became taxable.
A decade later, Congress added a steeper tier through the Omnibus Budget Reconciliation Act of 1993. Single filers with combined income above $34,000 and joint filers above $44,000 could now have up to 85% of their benefits taxed, as codified in the enrolled statute and written into 26 U.S. Code Section 86. Both tiers are hard-coded dollar amounts with no annual adjustment clause.
That missing adjustment clause is the entire problem. Most federal tax provisions that interact with income, including standard deductions, bracket boundaries, and IRA contribution limits, are indexed to inflation so they keep pace with the economy. The Social Security thresholds are not. A $25,000 trigger in 1984 would need to be more than $75,000 today to have the same purchasing-power meaning, based on the Bureau of Labor Statistics’ CPI inflation calculator. Instead, it is still $25,000. Retirees with far less real-world buying power than the original targets now get caught.
More retirees cross the line every year
The Congressional Research Service tracked this expansion in its report RL32552, which uses IRS Statistics of Income data and Social Security actuarial projections to show that the share of beneficiaries paying federal tax on their benefits has grown steadily for the precise reason that the thresholds are not indexed. That analysis was last updated in 2020, so exact counts for 2025 or 2026 are not available. But the directional trend is arithmetic, not speculation: each year, rising nominal incomes from pensions, required minimum distributions, part-time wages, and even Social Security’s own cost-of-living adjustments push more households above the fixed lines.
The cost-of-living adjustment, or COLA, deserves special attention here. Because the combined income formula counts half of Social Security benefits, a COLA designed to help retirees keep up with rising prices simultaneously increases the number that gets measured against the threshold. The 3.2% COLA that took effect in January 2024, the 2.5% COLA for January 2025, and the 2.4% COLA for January 2026 all raised the Social Security component of combined income for every recipient. For a retiree sitting just below a threshold, a COLA alone can push them over, even if their pension, savings withdrawals, and every other income source stayed exactly the same.
A concrete example of how the math hits
Consider a single retiree in 2026 with $18,000 in pension income, $4,000 in interest from a certificate of deposit, and $21,600 in annual Social Security benefits ($1,800 per month). Her combined income calculation looks like this:
- Adjusted gross income (pension + CD interest): $22,000
- Plus half of Social Security benefits: $10,800
- Combined income: $32,800
That figure clears the $25,000 threshold for the 50% inclusion tier and nearly reaches the $34,000 mark for the 85% tier. Under the lower tier, up to $10,800 of her $21,600 in benefits (50%) could be added to her taxable income. At a 12% marginal federal tax rate, that translates to roughly $1,296 in federal tax on benefits she may have assumed would arrive tax-free. If her CD earns a little more next year, or if the next COLA bumps her Social Security by a few hundred dollars, she crosses into the 85% tier, and the taxable portion jumps sharply.
None of this requires her actual standard of living to improve. Inflation pushes the numbers up; the thresholds stay put.
Where the tax revenue goes, and why that blocks reform
Revenue from taxing Social Security benefits does not vanish into the general fund. According to a Social Security Administration policy analysis, revenue from the original 50% inclusion tier is credited to the Old-Age, Survivors, and Disability Insurance (OASDI) trust funds, while revenue from the 85% tier flows to the Medicare Hospital Insurance (HI) trust fund.
That dual funding role turns every proposed fix into a budget standoff. Indexing the thresholds to inflation would restore the original intent of targeting only higher-income beneficiaries, but it would also shrink revenue flowing into Social Security and Medicare at a time when both programs face projected long-term shortfalls. Eliminating benefit taxation entirely would cost far more. Leaving the thresholds frozen, by contrast, gradually broadens the tax base without requiring any lawmaker to cast an explicit vote to raise taxes on retirees. It is a tax increase that runs on autopilot.
Repeal bills keep arriving, and keep stalling
Proposals to change the system surface in nearly every session of Congress. During the 118th Congress (2023-2024), the Social Security Tax Fairness Act (H.R. 3688) sought to repeal the taxation of benefits entirely, and the Senior Citizens Tax Elimination Act (H.R. 1040) pursued the same goal through a different legislative path. Similar measures have been introduced in the 119th Congress, though as of mid-2026 specific bill numbers for the reintroduced versions have not been confirmed as enacted or advanced out of committee. During the 2024 presidential campaign, then-candidate Donald Trump called for ending taxes on Social Security benefits altogether, a pledge that generated significant attention among retiree advocacy groups.
None of these efforts has resulted in a signed law. The political math is punishing: any bill that reduces revenue to the trust funds must either identify offsetting savings or accept a faster depletion timeline for Social Security and Medicare. As of mid-2026, the same dollar figures from 1984 and 1993 remain in effect under Section 86, unchanged.
Steps retirees can take now
Waiting for Congress to act is not a retirement plan. For anyone collecting Social Security or approaching their filing date, the most useful first step is running the combined income formula with their own numbers: adjusted gross income, plus tax-exempt interest, plus half of annual Social Security benefits. If the total exceeds $25,000 (single) or $32,000 (joint), some benefits will be taxed. Above $34,000 (single) or $44,000 (joint), up to 85% of benefits can be taxed.
Several strategies can help manage the impact in specific years:
- Roth conversions before claiming Social Security. Converting traditional IRA funds to a Roth IRA triggers taxable income in the conversion year, but qualified Roth withdrawals later do not count toward combined income. Doing conversions in the gap years between retirement and Social Security filing can pay off significantly.
- Sequencing retirement account withdrawals. Drawing down taxable accounts or Roth accounts in years when Social Security income is high can keep combined income below a threshold. The order matters more than most retirees realize.
- Coordinating the Social Security start date with other income. Delaying benefits to age 70 increases the monthly check but also increases the Social Security component of combined income. For some retirees, the higher benefit is still the better choice; for others near a threshold, the timing trade-off is worth modeling carefully.
State taxes add yet another layer. As of 2025, a small number of states still tax Social Security benefits to varying degrees, though several, including Nebraska, Missouri, and Kansas, have recently moved to exempt them. Retirees should verify their own state’s current rules alongside the federal thresholds.
Frozen in 1984, still collecting in 2026
The underlying dynamic is straightforward and well-documented: fixed dollar thresholds in a rising-income economy function as an automatic, silent tax increase. Congress does not need to pass new legislation for more retirees to owe tax on their Social Security. Inflation and wage growth do the work on their own, year after year, against lines drawn in 1984 and 1993 that have not moved a single dollar. Until lawmakers revisit Section 86, every COLA, every modest pension bump, and every required minimum distribution will keep pulling more beneficiaries into a tax they never expected to pay.
