Updated October 17, 2026. Quick answer: Lines 17l to 17q each take an amount that is figured on another form. Line 17l comes from Form 4970, 17n from Form 8697 or 8866, and 17p and 17q from Form 8621. Line 17m is an excise tax under section 4985, and line 17o is a tax for nonresident aliens. Copy the amount from the named form onto the line.
Lines 17l and 17m: trusts and expatriated corporations
Line 17l is captioned “Tax on accumulation distribution of trusts”. The instructions say “Enter any tax on accumulation distribution of trusts. See Form” 4970 for more information. Trust income is reported to beneficiaries on statements such as the ones explained on the Schedule K-1 (Form 1041) page, and the trust’s own return is covered on the Form 1041 page.
Line 17m is captioned “Excise tax on insider stock compensation from an expatriated corporation”. The instructions say “Enter any excise tax on insider stock compensation from an expatriated corporation. See section 4985.”
Lines 17n and 17o: lookback interest and nonresident aliens
Line 17n is captioned “Lookback interest under section 167(g) or 460(b) from Form 8697 or 8866”. The instructions say “Enter any look-back interest” under section 167(g) or 460(b), and they add “See Form 8697 or 8866 for more information.”
Line 17o is the tax a nonresident alien owes on income that is not effectively connected, taken from Form 1040-NR. The instructions say “Enter any tax on non-effectively connected income for any part of the year you were a nonresident alien.” “See the Instructions for Form 1040-NR for more information.”
Lines 17p and 17q: interest from Form 8621
Line 17p is captioned “Any interest from Form 8621, line 16f, relating to distributions from, and” dispositions of, stock of a section 1291 fund. The instructions say “Enter any interest amount from Form 8621, line 16f, relating to distributions from, and dispositions of, stock of a section 1291 fund.”
Line 17q is captioned “Any interest from Form 8621, line 24”. The instructions say “Enter any interest amount from Form 8621, line 24.” The form itself is explained on the Form 8621 page.
Where the number comes from
Every line in this group points to another form or section: Form 4970, section 4985, Form 8697 or 8866, Form 1040-NR, and Form 8621. The line asks for a result from that form, so complete the other form first and then enter the amount it names.
Where it goes next
These lines belong to the line 17 list, and the form’s caption for line 18 reads “Total additional taxes. Add lines 17a through 17z”. That total is covered in Schedule 2 lines 17z and 18. The layout of the whole schedule is on the Schedule 2 (Form 1040) page, and the return it attaches to is explained on the Form 1040 page.
Edition and line numbers
This page reads the 2025 Schedule 2 (Form 1040) and the 2025 Form 1040 instructions, the current files irs.gov served on 2026-10-17. They are the files for the tax year 2025 return, filed in 2026. The schedule says “Attach to Form 1040, 1040-SR, or 1040-NR.” Its line instructions are part of the Form 1040 instructions, under the heading “Instructions for Schedule 2”. Check the tax year printed on the schedule you are filling in and use the line numbers on that year’s schedule, because a different year’s schedule can number or word its lines differently.
Common mistakes
- Estimating the trust tax on line 17l. The instructions send you to another form: “See Form” 4970 for more information.
- Entering the wrong Form 8621 line on line 17p or 17q. Line 17p takes “Enter any interest amount from Form 8621, line 16f” and line 17q takes “Enter any interest amount from Form 8621, line 24.”
- Skipping the form named on line 17n. The instructions say “See Form 8697 or 8866 for more information.”
Related: Form 8621, Form 1041, Schedule K-1 (Form 1041), and Form 1040.
Sources
- Instructions for Form 1040 and Form 1040-SR (2025): https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
- Schedule 2 (Form 1040), Additional Taxes (2025): https://www.irs.gov/pub/irs-pdf/f1040s2.pdf
Read from the IRS documents linked above on October 17, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.