What this line means
The Section 199A qualified business income deduction in three columns. This deduction — up to 20% of qualified business income from pass-through entities, sole proprietorships, or rental activities — reduces taxable income but is separate from the standard or itemized deduction on line 2. Column A is the original deduction, Column B is the change, Column C is the corrected amount.
Does this apply to you?
- You discovered additional qualified business income that changes your Section 199A deduction
- You incorrectly calculated the deduction on your original return
- You received a corrected Schedule K-1 from a partnership or S corporation
- You are adding or removing self-employment income that affects the QBI deduction
- You did not claim the deduction on your original return but were eligible
Easy to overlook
The QBI deduction recalculates when AGI changes The qualified business income deduction phases out for specified service trades or businesses when taxable income exceeds $197,300 (single) or $394,600 (married filing jointly) for 2025. If your amendment changes AGI enough to cross this threshold, the QBI deduction itself changes. Recalculate Form 8995 or 8995-A with the corrected taxable income. 1 IRS Form 1040-X Instructions — Line 4
Attach corrected Form 8995 or 8995-A If line 4 changes, attach the recalculated QBI deduction form. Form 8995 is the simplified version; Form 8995-A is for filers above the phase-out threshold or with multiple businesses. Omitting the supporting form delays processing because the IRS cannot verify the corrected deduction. 2 IRS Form 8995 Instructions — Qualified Business Income Deduction
Watch out for this
Leaving line 4 unchanged when amending income that includes qualified business income. If you add or remove self-employment income, rental income, or K-1 income on the amendment, the QBI deduction almost certainly changes. Leaving the original deduction amount in Column C when the underlying income changed produces an inconsistent return.
Footnotes
-
IRS Form 1040-X Instructions, Line 4. https://www.irs.gov/instructions/i1040x ↩
-
IRS Form 8995 Instructions, Qualified Business Income Deduction. https://www.irs.gov/instructions/i8995 ↩