Form 1040

17 — Additional Tax from Schedule 2 Updated for tax year 2025

What this line means

Additional taxes from Schedule 2, Part I that are added to your regular income tax on line 16. The most common additional taxes here are the Alternative Minimum Tax (AMT) and the excess premium tax credit repayment. These taxes apply on top of your regular tax — they are not credits or deductions but extra tax liability.

Does this apply to you?

  • You are subject to the Alternative Minimum Tax (AMT) due to high income or large deductions
  • You received advance premium tax credits for ACA health insurance and need to repay some or all of the advance
  • You owe the tax on early distributions from retirement plans (10% penalty)
  • You have other taxes calculated on Schedule 2, Part I

Easy to overlook

The AMT catches more people than you think The Alternative Minimum Tax was designed for high-income taxpayers, but it can affect upper-middle-income filers with large state and local tax deductions, significant long-term capital gains, or incentive stock option exercises. The $88,100 (single) / $137,000 (MFJ) AMT exemption covers most filers, but the exemption phases out starting at $626,350 (single) / $1,252,700 (MFJ). 1 [SOURCE: IRS Schedule 2 instructions — Additional Taxes]

ACA premium tax credit repayment can be substantial If your actual income for the year exceeded the estimate you gave to the health insurance marketplace, you may owe back some or all of the premium tax credits you received in advance. This repayment shows up on Schedule 2 and increases your tax on line 17. The surprise is often large for filers who had a good income year after enrolling with a low-income estimate. 2 [SOURCE: General filing pattern — AMT not calculated when required]

Watch out for this

Not completing Schedule 2 when required. If you exercised incentive stock options, have significant income from private activity bonds, or received advance premium tax credits, you need to check whether Schedule 2 applies. Tax software handles this automatically, but paper filers sometimes skip the schedule and underreport their tax.

  • Line 16 — Form 1040 — Regular tax; line 17 is added to this
  • Line 18 — Form 1040 — Total tax before credits; the sum of lines 16 and 17
  • Form 6251 — Alternative Minimum Tax — the detailed AMT calculation

Footnotes

  1. IRS Schedule 2 (Form 1040) Instructions, Part I (Tax). https://www.irs.gov/instructions/i1040s2 ↩

  2. IRS Form 1040 Instructions. See also IRS Publication 17, Your Federal Income Tax. https://www.irs.gov/pub/irs-pdf/p17.pdf ↩

Back to top