Updated October 17, 2026. Quick answer: Lines 7 and 8 are the totals of Part I, Nonrefundable Credits, on Schedule 3. Line 7 adds the line 6 credits, lines 6a through 6z. Line 8 adds lines 1 through 4, 5a, 5b and 7, and that total goes on Form 1040 line 20.
Line 7: total other nonrefundable credits
Part I of the schedule is headed “Nonrefundable Credits”. Line 7 is captioned “Total other nonrefundable credits. Add lines 6a through 6z”. It has no instruction paragraph of its own: it is the sum of the line 6 entries covered on Schedule 3 lines 6a to 6e, Schedule 3 lines 6f to 6k and Schedule 3 lines 6l, 6m and 6z.
Line 8: the Part I total
Line 8 is captioned “Add lines 1 through 4, 5a, 5b, and 7. Enter here and on Form 1040, 1040-SR, or 1040-NR, line 20”. In other words, it adds the credits on Schedule 3 line 1, Schedule 3 line 2, Schedule 3 line 3, Schedule 3 line 4 and Schedule 3 lines 5a and 5b, plus the line 7 total.
Where the number comes from
Both lines are sums of lines already on the schedule. The General Instructions describe when the schedule is used: “Use Schedule 3 if you have nonrefundable credits, other than the child tax credit or the credit for other dependents, or other payments and refundable credits.”
Where it goes next
The General Instructions say “Include the amount on Schedule 3, line 8, in the amount entered on Form 1040, 1040-SR, or 1040-NR, line 20.” The Form 1040 lines 19, 20 and 21 page explains line 20 on the return. Line 8 is the end of Part I; Part II, Other Payments and Refundable Credits, starts at Schedule 3 line 9. The Form 1040 page explains the return.
Edition and line numbers
This page reads the 2025 Schedule 3 (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.” Schedule 3 has no separate instructions booklet. Its line instructions are part of the Form 1040 instructions, under the heading “Instructions for Schedule 3”. 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
- Leaving the child tax credit or credit for other dependents on Schedule 3. The General Instructions describe the schedule as for “nonrefundable credits, other than the child tax credit or the credit for other dependents”
- Adding line 6 entries again on line 8. The caption adds “Add lines 1 through 4, 5a, 5b, and 7.” and line 7 already totals the line 6 entries.
- Carrying line 8 to the wrong Form 1040 line. The caption says “Enter here and on Form 1040, 1040-SR, or 1040-NR, line 20”
Related: Form 1040 lines 19, 20 and 21, and Form 1040.
Sources
- Instructions for Form 1040 and Form 1040-SR (2025): https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
- Schedule 3 (Form 1040), Additional Credits and Payments (2025): https://www.irs.gov/pub/irs-pdf/f1040s3.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.