$OBBBA Calculators
← W-4 Withholding Adjuster

Firefighter Withholding Calculator

For fire service on FLSA 7(k) cycles.

The short answer: At the scenario numbers pre-loaded below, the OBBBA deductions total $4,500, worth about $540 in federal income tax at a 12% marginal rate ($21 per biweekly paycheck) — that's the gap your W-4 can capture during the year.

Total OBBBA above-the-line deductions: $4,500
Extra tax you are on track to over-withhold: $540
≈ $21 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

7(k) work periods still generate OT past the FLSA threshold — premium dollars feed the 4(b) entry.

  • • Premium beyond the work-period threshold → deductible
  • • Kelly-day pickups add premium hours
  • • Strike-team deployments count if premium-paid

Worked Example

A firefighter at $30/hour, 300 OT hours.

  • • Total OBBBA deductions: $4,500
  • • Federal income tax savings: $540 at the 12% marginal rate
  • • Per biweekly paycheck: $21 — capture it via a W-4 4(b) adjustment instead of waiting for refund season

Keep Reading

Frequently Asked Questions

Do 7(k) schedules change the W-4 math?

They change when OT accrues, not the deduction: premium dollars reported on W-2 go into the 4(b) estimate.

Deployment pay?

Premium-paid deployment hours past the threshold count like any OT.