Updated October 17, 2026. Quick answer: Line 13a is the qualified business income deduction, figured on Form 8995 or Form 8995-A. Line 13b is for additional deductions, and the amount comes from Schedule 1-A, line 38. Both lines are copied from another form, and both are added into the deductions total on line 14.
More IRS forms for employers and business owners, read line by line: Form 8995-A Schedule A and Form 8995-A Schedule D.
Read box by box from the IRS form text: Form 1099-PATR boxes 6 to 9.
Business use of your home (Form 8829), the saver’s credit (Form 8880), clean vehicle credits (Form 8936) and amended returns (Form 1040-X), read line by line: Form 1040-X lines 1 to 3 and Form 1040-X lines 4a to 5.
Schedule C and Schedule SE (Form 1040) for 2025, read line by line: Schedule C lines 31 and 32.
What lines 13a and 13b ask for
The form’s caption for line 13a reads “Qualified business income deduction from Form 8995 or Form 8995-A”. The caption for line 13b reads “Additional deductions from Schedule 1-A, line 38”. Neither line is figured on the front of Form 1040. Each one is a copy of a result worked out on another form. The rest of the return is mapped in Form 1040 line by line.
Line 13a: the qualified business income deduction
The instructions begin with the form to use: “To figure your Qualified Business Income Deduction, use Form 8995 or Form 8995-A as applicable.” Form 8995 has its own page at the Form 8995 page.
The instructions say when the shorter Form 8995 is allowed. The first condition is “You have qualified business income, qualified REIT dividends, or qualified PTP income (loss);”
The second is a limit on taxable income: “Your 2025 taxable income before the qualified business income deduction is less than or equal to $197,300 ($394,600 if married filing jointly);” The third is “You aren’t a patron in a specified agricultural or horticultural cooperative.”
If you do not meet those requirements, “use Form 8995-A, Qualified Business Income Deduction.” “Attach whichever form you use (Form 8995 or 8995-A) to your return.” For the thresholds as they apply to later years, see the QBI deduction thresholds page; the figures above are the ones the 2025 instructions print.
Line 13b: additional deductions from Schedule 1-A
The instructions describe the line this way: “If you are eligible to claim a deduction for no tax on tips, no tax on overtime, no tax on car loan interest, and/or the enhanced deduction for seniors, enter on line 13b the amount, if any, from Schedule 1-A, line 38.” The instructions then send you onward: “See Schedule 1-A and the instructions for Schedule 1-A for more information.”
Line 13b is therefore not a place to estimate a deduction. It is a single number taken from line 38 of Schedule 1-A, and the instructions say to enter the amount, if any.
Where the number comes from
Both numbers come from forms you complete before you reach line 13. Line 13a comes from Form 8995 or Form 8995-A, which in turn use business income, REIT dividends or publicly traded partnership income reported on other forms. If your business income comes from a sole proprietorship, that income starts on the Schedule C page. Line 13b comes from Schedule 1-A, line 38. Work out those forms first, then copy the results to the Form 1040. Keep the attached form with your return so the number on the line can be traced back to its source.
Where it goes next
The form adds line 13 to the standard or itemized deduction. The caption for line 14 reads “Add lines 12e, 13a, and 13b”. The total on line 14 is then subtracted from adjusted gross income to reach taxable income. The line 12e amount is explained on line 12, and the totals are explained on lines 14 and 15.
Edition and line numbers
This page reads the 2025 Form 1040 and its 2025 instructions, the current files irs.gov served on 2026-10-17. They are the forms for the tax year 2025 return, filed in 2026. The instructions say “The lines on Forms 1040 and 1040-SR are the same.” so everything here applies to Form 1040 and to Form 1040-SR alike. The Form 8995 dollar figures quoted above are the ones printed in those instructions. Check the tax year printed on the form you are filling in and use the line numbers on that year’s form, because a different year’s form can number or word its lines differently.
Common mistakes
- Using Form 8995 when you are over the taxable income limit. The instructions say “If you don’t meet these requirements, use Form 8995-A, Qualified Business Income Deduction.”
- Forgetting to attach the form. The instructions say “Attach whichever form you use (Form 8995 or 8995-A) to your return.”
- Entering an estimate on line 13b. The instructions say to enter “the amount, if any, from Schedule 1-A, line 38.”
Related: Form 8995, QBI deduction thresholds, Schedule C (Form 1040), and Form 1040.
Sources
- Instructions for Form 1040 and Form 1040-SR (2025): https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
- Form 1040, U.S. Individual Income Tax Return (2025): https://www.irs.gov/pub/irs-pdf/f1040.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.