OBBBA provision formulas (2026)
| Provision | Cap / amount | Phase-out | Code |
|---|---|---|---|
| No Tax on Tips | Deduct ≤ $25,000 of tips | −$100 / $1,000 MAGI over $150k (S) / $300k (MFJ) | §224 |
| No Tax on Overtime | Deduct premium ≤ $12,500 (S) / $25,000 (MFJ) | same as tips | §225 |
| Senior Bonus Deduction | $6,000/person 65+ ($12,000 both) | −6% of MAGI over $75k (S) / $150k (MFJ) | §151(d)(5) |
| Car Loan Interest | Deduct ≤ $10,000 of interest | −$200 / $1,000 over $100k (S) / $200k (MFJ) | §163(h)(4) |
| Child Tax Credit | $2,200/child (refundable ≤ $1,700) | −$50 / $1,000 over $200k (S) / $400k (MFJ) | §24 |
| SALT cap | $40,400 (2026); floor $10,000 | −30% of MAGI over $505,000 | §164(b)(6) |
| RAP student loan | 1–10% of AGI ÷ 12, −$50/dependent, $10 min | n/a | P.L. 119-21 |
How FedCalc computes your savings
For a deduction, your benefit is not the deduction amount — it's the deduction times your marginal tax rate. We compute it bracket-by-bracket for accuracy, not as a flat estimate:
- Deduction savings = tax owed on (income − standard deduction) minus tax owed on (income − standard deduction − the OBBBA deduction). This correctly handles a deduction that straddles a bracket boundary.
- Phase-outs are applied to the deduction/credit before valuing it, using your income as a MAGI proxy (exact for most filers).
- The master "Total Tax Change" tool stacks all deductions on taxable income and values them together, then adds the Child Tax Credit — so the breakdown always sums to the headline.
- Caps are enforced (e.g., tips deduction stops at $25,000), and the same dollar can't count for two provisions.
Our math is covered by an open regression test suite, so a future change can't silently alter a published number.
A note on accuracy & freshness
These figures reflect the enacted statute (P.L. 119-21) and IRS guidance as of June 2026. Several OBBBA provisions are still being finalized in regulations; where a detail is not yet settled we label it Provisional on the relevant calculator. Most of these deductions apply for tax years 2025–2028 and then expire; the SALT cap reverts to $10,000 in 2030. We update this page when the IRS issues new guidance.
Primary sources
Disclaimer: Educational reference based on the 2026 OBBBA statute and IRS guidance. Not tax advice. FedCalc is independent and not affiliated with the U.S. government or IRS.