Biden Tax Plan Calculator

Compare 2026 current-law tax against the FY2025 Biden proposal scenario with higher top rates, capital-gains changes, and a higher NIIT rate.

About the Biden Tax Plan Calculator

This calculator compares 2026 current-law federal tax against the FY2025 Treasury proposal associated with the Biden administration. The current-law side uses the 2026 IRS brackets, standard deductions, capital-gains thresholds, and NIIT rules. The proposal side models the Greenbook changes most relevant to high earners: a 39.6% top ordinary rate above the stated thresholds, ordinary-rate treatment for capital gains and qualified dividends above the proposal threshold, and a higher NIIT rate on investment income above the proposal threshold.

The calculator is a scenario tool, not an enacted-law filing system. Use it to see which layer of tax changes first: ordinary income, capital gains, or NIIT.

Why Use This Biden Tax Plan Calculator?

Tax planning requires understanding both current law and the policy direction that would matter if a proposal became law. This calculator helps higher-income taxpayers model how the top bracket, capital gains treatment, and NIIT changes would alter the result without pretending the proposal has already been enacted.

How to Use This Calculator

  1. Enter your gross annual income
  2. Select your filing status
  3. Enter deductions, or start from the standard deduction shown
  4. Add capital gains and qualified dividends if applicable
  5. Compare the current-law tax and the proposal scenario
  6. Review the breakdown by tax component
  7. Use presets to model common income ranges

Formula

Current law (2026): ordinary brackets, capital gains rates, and NIIT follow IRS 2026 thresholds by filing status. FY2025 proposal: 39.6% top ordinary rate above $400,000 single, $225,000 MFS, $425,000 HOH, and $450,000 MFJ/QSS; capital gains and qualified dividends taxed at ordinary rates above $1,000,000 taxable income ($500,000 MFS); NIIT increased to 5% above the proposal threshold.

Example Calculation

Result: Current law $148,484 vs proposal $153,004

At this income level, the current-law side uses the 2026 brackets and the 15% long-term capital-gains rate, while the proposal pushes ordinary income above the status threshold to 39.6% and raises NIIT on investment income above the proposal threshold. The gap is driven mostly by the ordinary-income portion.

Tips & Best Practices

What This Models

This calculator compares 2026 current law against the FY2025 Treasury proposal. The baseline uses the IRS 2026 brackets and capital-gains thresholds, while the proposal replaces the top ordinary rate and changes how very large capital gains and dividends are treated.

When It Matters

The difference is usually concentrated at the top ordinary bracket and then widens if the taxpayer has substantial investment income. Filing status matters because the proposal thresholds are not the same for every filer.

Key Checkpoints

Use the comparison to separate ordinary income effects from investment-income effects, then verify deductions and filing status before relying on the result for planning.

Sources & Methodology

Last updated:

Methodology

Baseline calculations use IRS-published 2026 inflation-adjusted amounts for ordinary brackets, standard deductions, long-term capital-gains thresholds, and the 3.8% NIIT threshold. The proposal side is a static FY2025 Treasury Greenbook scenario: it keeps the baseline bracket stack up to the proposal threshold, then applies the proposed 39.6% top ordinary rate, ordinary treatment of capital gains and qualified dividends above the proposal threshold, and the proposed 5% NIIT rate above the proposal threshold.

Sources

Frequently Asked Questions

Who would pay more under the proposal?

The biggest differences show up for higher-income taxpayers, especially those above the proposal threshold for ordinary income or with substantial capital gains and dividends.

What is the proposed top tax rate?

The FY2025 proposal raises the top ordinary rate to 39.6% above the status-specific threshold used on this page.

How would capital gains be taxed?

The proposal models capital gains and qualified dividends as ordinary income above the taxable-income threshold shown in the calculator.

When would these changes take effect?

This is a scenario tool for the FY2025 proposal, not enacted law. Real-world timing depends on legislation and effective dates.

Does the proposal affect the standard deduction?

The comparison keeps the 2026 current-law standard deductions on the baseline side. The proposal side changes the tax rates and investment-income treatment rather than rewriting the deduction input.

What about the Net Investment Income Tax?

The current-law NIIT remains 3.8%. The proposal models a higher 5% rate above the proposal threshold for investment income.

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