How to Fill Out Schedule 1-A: Step-by-Step Instructions
Schedule 1-A is the new IRS form for claiming OBBBA deductions on your 2025 federal tax return. This guide walks you through every section of the form so you can fill it out correctly and maximize your deductions.
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What Is Schedule 1-A?
Schedule 1-A is a supplemental form attached to your Form 1040 that was introduced for the 2025 tax year. The IRS released this form in March 2026 to accommodate the four new below-the-line deductions created by the One Big Beautiful Bill Act (OBBBA), which was signed into law on July 4, 2025.
Unlike Schedule 1 (which handles above-the-line adjustments to income), Schedule 1-A deductions reduce your taxable income directly without changing your AGI. This is important because it means these deductions do not affect income-based calculations for other tax benefits like IRA contributions or student loan interest deductions.
The total of all your Schedule 1-A deductions is entered on Form 1040, Line 13b. You can claim these deductions whether you take the standard deduction or itemize on Schedule A — they are additional deductions available to all qualifying taxpayers.
Before You Begin: Documents You Need
Gather these documents before filling out Schedule 1-A to make the process smooth:
- Form W-2 — Box 7 shows your reported tip income; Box 14 may show overtime premium if your employer reported it separately.
- Form 1098-VLI — Your auto lender sends this showing qualifying vehicle loan interest paid during the year.
- Pay stubs — If your W-2 does not break out overtime premium, you can calculate it from your pay stubs (overtime hours multiplied by the premium rate).
- Date of birth — Needed to determine eligibility for the senior deduction (must be 65 or older by December 31, 2025).
- Form 1040 Line 11 — Your Adjusted Gross Income (AGI) is needed for MAGI calculations and phase-out determinations.
Part I: Modified Adjusted Gross Income (MAGI)
Part I of Schedule 1-A calculates your Modified Adjusted Gross Income, which is used to determine phase-out amounts for each deduction. For most taxpayers, MAGI is simply equal to AGI.
If you did not exclude foreign or territory income, Lines 2-4 are zero and your MAGI equals your AGI. Most taxpayers can simply copy their AGI from Form 1040, Line 11 to Line 5.
Part II: No Tax on Tips Deduction
Complete Part II if you received qualified tip income during 2025. This section calculates your tips deduction after applying the $25,000 cap and any MAGI-based phase-out.
Enter your total qualified tips from W-2 Box 7 on Line 6. If you are self-employed and received tips, enter the lesser of your tip income or net business profit from Schedule C. The form automatically caps the deduction at $25,000.
Lines 7-8 calculate any phase-out reduction based on your MAGI from Line 5. If your MAGI exceeds $150,000 (Single/HOH/QSS) or $300,000 (MFJ), the worksheet on the form walks you through the reduction calculation — $100 for every $1,000 over the threshold, with partial thousands rounded up.
Line 9 shows your final tips deduction after caps and phase-outs. If you file Married Filing Separately, enter zero on Line 9 — MFS filers cannot claim this deduction.
Part III: No Tax on Overtime Deduction
Part III applies if you received overtime premium pay during 2025. Remember that only the premium portion of overtime pay qualifies — not the entire overtime wage.
On Line 10, enter your qualified overtime premium. This is the amount above your regular hourly rate for each overtime hour. For time-and-a-half pay, the premium is 0.5 times your regular rate multiplied by overtime hours. Check W-2 Box 14 or calculate from pay stubs.
The deduction is capped at $12,500 for most filers or $25,000 for MFJ. The phase-out calculation on Lines 11-12 uses the same thresholds and rate as the tips deduction ($150K/$300K, $100 per $1,000 excess).
MFS filers should enter zero. The final overtime deduction appears on Line 13.
Part IV: Car Loan Interest Deduction
Part IV covers the deduction for interest paid on qualifying vehicle loans. This is the only Schedule 1-A deduction available to MFS filers.
Enter your total qualifying vehicle loan interest from Form 1098-VLI on the first line. If you also deducted any of this interest on Schedule C, E, or F (for business use), subtract that amount. The net eligible interest is then capped at $10,000.
The phase-out for car loan interest uses different thresholds than tips and overtime: $100,000 for Single/HOH/MFS and $200,000 for MFJ. The reduction rate is also steeper at $200 per $1,000 over the threshold, meaning the deduction is fully phased out at $150,000 (Single) or $250,000 (MFJ).
The vehicle must be new, US-assembled, and purchased between January 1, 2025 and December 31, 2028 to qualify.
Part V: Enhanced Senior Deduction
Part V provides an additional $6,000 deduction per qualifying individual age 65 or older. If filing MFJ and both spouses qualify, the maximum is $12,000.
Eligibility is straightforward: enter your date of birth and your Social Security number. The form determines whether you were 65 or older by December 31, 2025 (born before January 2, 1961). For MFJ, repeat for your spouse.
The phase-out for the senior deduction works differently from the other three deductions. Instead of a flat dollar reduction per $1,000, the senior deduction is reduced by 6% of the amount your MAGI exceeds the threshold ($75,000 Single / $150,000 MFJ). This calculation uses the exact dollar amount with no rounding.
The deduction is fully phased out when MAGI reaches $175,000 (Single) or $250,000 (MFJ). No earned income is required — retirees with only Social Security or pension income can claim this deduction.
Line 13b: Your Total Schedule 1-A Deduction
After completing all applicable Parts, add up your deductions from Parts II through V. This total goes on Line 13b of Schedule 1-A and is then transferred to Form 1040, Line 13b.
This amount reduces your taxable income below the line. It is applied after your standard deduction or itemized deductions, providing an additional reduction in taxable income. Even taxpayers with zero federal income tax liability should file Schedule 1-A if they qualify, as it establishes a record with the IRS.
Common Mistakes to Avoid
- Deducting full overtime pay instead of just the premium — Only the amount above your regular rate qualifies. If you earn $20/hr regular and $30/hr overtime, deduct only the $10/hr premium.
- MFS filers claiming tips, overtime, or senior deductions — Only the car loan interest deduction is available to MFS filers. The other three require a different filing status.
- Forgetting to subtract business-use interest from car loan — If you already deducted vehicle loan interest on Schedule C, E, or F, you cannot double-deduct it on Schedule 1-A.
- Using AGI instead of MAGI for phase-outs — While they are the same for most people, if you excluded foreign or territory income, your MAGI may be higher than your AGI.
- Not filing Schedule 1-A at all — Many eligible seniors do not realize they qualify for the new $6,000 deduction. If you are 65+ with MAGI under $175,000, check whether this deduction applies to you.