Can I claim all four deductions?

Yes — if you qualify for each one independently. Overtime and tips require W-2 employment. The car loan deduction requires a qualifying vehicle assembled in the U.S. The senior deduction requires age 65+.

Does this work for self-employed or 1099 contractors?

No. The overtime and tips deductions only apply to W-2 employees. Self-employed income does not qualify.

Is FICA (Social Security and Medicare) included?

No. FICA taxes still apply to all wages, including overtime and tips. These deductions only reduce federal income tax.

← W-4 Withholding Adjuster

W-4 Line 4(b) OBBBA Calculator

For anyone converting deductions into a W-4 number.

The short answer: At the scenario numbers pre-loaded below, the OBBBA deductions total $9,200, worth about $1,104 in federal income tax at a 12% marginal rate ($42 per biweekly paycheck) — that's the gap your W-4 can capture during the year.

Filing StatusAnnual Income (MAGI)All wages + tips, before deductionsHourly RateRegular rateAnnual Overtime HoursAnnual Tip Income0 if noneVehicle Loan Interest0 if noneYour AgeSpouse Age

Federal Income Tax Withheld This Year (paystubs YTD)Your payroll is likely withholding as if none of the OBBBA deductions exist

Total OBBBA above-the-line deductions: $9,200

Extra tax you are on track to over-withhold: $1,104

≈ $42 per biweekly paycheck

File a revised W-4 (Step 4a "other income" negative adjustment or dependents/credits line) to bring this money home in each paycheck instead of waiting for a refund.

⚠️ This calculator provides estimates for informational and educational purposes only. It is not tax advice. Results are based on the One Big Beautiful Bill Act (OBBBA) and IRS Schedule 1-A. Consult a qualified tax professional for your specific situation.

Withholding vs. What You Actually Owe

Line 4(b) wants annual deduction dollars, not tax dollars. Enter the OBBBA deduction total; the tables reduce withholding by your marginal rate automatically.

• 4(b) = OT premium deduction + tips deduction + car interest + senior bonus
• Don't forget the caps and phase-out when estimating
• Recheck mid-year if OT patterns shift

Worked Example

A worker combining OT and car-loan interest.

• Total OBBBA deductions: $9,200
• Federal income tax savings: $1,104 at the 12% marginal rate
• Per biweekly paycheck: $42 — capture it via a W-4 4(b) adjustment instead of waiting for refund season

Keep Reading

• /withholding/
• /rules/

Frequently Asked Questions

What goes on W-4 line 4(b) for OBBBA deductions?

The estimated annual dollar total of your OBBBA deductions (premium pay, tips, car interest, senior bonus) — the withholding tables apply your tax rate.

Is there a risk of under-withholding?

If you overestimate deductions, yes. Stay within safe harbors (90% of current tax or 100/110% of last year's).