Schedule 1-A Combined Deduction Estimator
This calculator estimates your total Schedule 1-A additional deductions for 2025 to 2028: no tax on tips, no tax on overtime, car loan interest, and the enhanced deduction for seniors, totalled for Form 1040, line 13b.
How this is calculated
Schedule 1-A (Form 1040) totals four above-the-line deductions created by the One Big Beautiful Bill Act, available for tax years 2025 through 2028 whether or not you itemize. Each part has its own cap and its own modified adjusted gross income (MAGI) phaseout, then all four are added together on Part VI, line 38.
| Deduction | Annual cap | Phaseout starts (single) | Phaseout starts (MFJ) |
|---|---|---|---|
| No tax on tips (Part II) | $25,000 | $150,000 | $300,000 |
| No tax on overtime (Part III) | $12,500 / $25,000 MFJ | $150,000 | $300,000 |
| Car loan interest (Part IV) | $10,000 | $100,000 | $200,000 |
| Senior deduction (Part V) | $6,000 per person | $75,000 | $150,000 |
No tax on tips (Part II) caps qualified tips at $25,000, phasing out above $150,000 MAGI ($300,000 married filing jointly) by $100 per $1,000 of excess MAGI. Only tips from an occupation on the IRS list of occupations that customarily and regularly received tips qualify.
No tax on overtime(Part III) only allows the FLSA-required premium (the "half" of "time and a half"), not your full overtime pay, capped at $12,500 ($25,000 married filing jointly), with the same phaseout mechanics as tips.
No tax on car loan interest (Part IV) caps interest at $10,000, phasing out above $100,000 MAGI ($200,000 married filing jointly) by $200 per $1,000 of excess MAGI, rounded up.
The enhanced deduction for seniors (Part V) gives up to $6,000 to each spouse who is 65 or older, phasing out continuously at 6% of MAGI above $75,000 ($150,000 married filing jointly), a straight-line reduction, not the stepped phaseout used by the other three parts.
All four require married taxpayers to file jointly to claim them, and all four use the same MAGI figure from Schedule 1-A, Part I.
Worked example
Suppose you are single with a MAGI of $70,000 for 2025, you received $12,000 in qualified tips, and you worked 200 overtime hours at time and a half on a $28 hourly rate, paid $8,400 for them. Your MAGI is below the phaseout threshold, so nothing is reduced, but only part of the overtime pay qualifies:
| Step | Amount |
|---|---|
| Qualified tips received (Part II) | $12,000 |
| Deductible tips | $12,000 |
| Overtime pay received | $8,400 |
| Deductible overtime: the FLSA premium only (Part III) | $2,800 |
| Total additional deductions (Part VI, line 38) | $14,800 |
Open this example in the calculator to change any figure.
Sources
Frequently asked questions
- Do I have to claim all four deductions?
- No. Toggle on only the parts that apply to you. Schedule 1-A itself works the same way, with each part completed only if you received that type of income.
- Why is my overtime deduction so much smaller than my total overtime pay?
- Only the FLSA-required premium (the "half" portion of "time and a half") counts as qualified overtime compensation, not your full overtime pay. If your employer pays more than the FLSA requires, the extra amount does not qualify.
- Can I claim the senior deduction alongside the standard deduction?
- Yes. It stacks on top of the existing additional standard deduction for taxpayers who are 65 or older, and on top of the standard deduction itself.
- Do tips from a specified service trade or business (SSTB) qualify?
- By statute, no, but IRS transition relief (Notice 2025-69) currently suspends enforcement of that exclusion. This calculator reflects the current transition relief and will be updated if final SSTB-specific regulations change it.
- What counts as MAGI for these deductions?
- Schedule 1-A defines MAGI, for this purpose, as your adjusted gross income (Form 1040, line 11b) plus any excluded Puerto Rico income and certain foreign earned income exclusions (Form 2555 and Form 4563). All four deductions use the same MAGI figure.
- Are these deductions available if I take the standard deduction?
- Yes. All four are above-the-line deductions claimed on Schedule 1-A, available whether you take the standard deduction or itemize on Schedule A.
- Are these deductions available after 2028?
- No. All four apply only to tax years 2025 through 2028, then lapse under current law.