Updated October 17, 2026. Quick answer: Lines 13 to 16 are four separate entries. Line 13 is tax shown in box 12 of Form W-2, line 14 and line 15 are interest on certain installment sales, and line 16 is recapture of the low-income housing credit taken from Form 8611. Each is added into the total other taxes on line 21.
Line 13: tax shown in box 12 of Form W-2
The form’s caption for line 13 reads “Uncollected social security and Medicare or RRTA tax on tips or group-term life insurance from Form” W-2, box 12. The instructions say where to look: “This tax should be shown in box 12 of Form W-2 with codes A and B or M and N.” So the amount is read off your Form W-2, not figured on a worksheet. The box 12 codes are explained on the page about W-2 box 12 codes A and B and on the overview of all W-2 box 12 codes.
Line 14: installment sales of residential lots and timeshares
The caption reads “Interest on tax due on installment income from the sale of certain residential lots and timeshares”. The instructions say “Enter interest on tax due on installment income from the sale of certain residential lots and timeshares under section” 453(l)(3). The form that reports installment sales is covered on the Form 6252 page.
Line 15: deferred tax on larger installment sales
The caption reads “Interest on the deferred tax on gain from certain installment sales with a sales price over $150,000”. The instructions say “Enter interest on the deferred tax on gain from certain installment sales with a sales price over $150,000 under section” 453A(c).
Line 16: recapture of the low-income housing credit
The caption reads “Recapture of low-income housing credit. Attach Form 8611”. The instruction is short: “Enter the amount from Form 8611, line 14.” Attach Form 8611 to the return, as the caption says.
Where it goes next
These four lines are added into line 21, whose caption reads “Add lines 4, 7 through 16, 18, and 19. These are your total other taxes. Enter here and on Form 1040 or 1040-SR, line 23”. Line 21 is covered on Schedule 2 lines 19 to 21. The line just before this group is on the page for Schedule 2 line 12, and the next group is on lines 17a and 17b. The schedule overall is on the Schedule 2 (Form 1040) page and the form it attaches to is Form 1040.
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
- Looking for a worksheet for line 13. The instructions say “This tax should be shown in box 12 of Form W-2 with codes A and B or M and N.”, so the amount is already on the W-2.
- Mixing up lines 14 and 15. Line 14 is interest “under section” 453(l)(3) on certain residential lots and timeshares, while line 15 is interest on a sale with “a sales price over $150,000” under section 453A(c).
- Entering the wrong figure for line 16. The instruction is “Enter the amount from Form 8611, line 14.”
Related: W-2 box 12 codes A and B, all W-2 box 12 codes, Form 6252, 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.