When Congress passed the OBBBA in July 2025, it created a federal tips deduction worth up to $25,000 per year. But whether that deduction also reduces state income tax depends entirely on how each state connects to the Internal Revenue Code. Colorado, Arizona, Iowa, and Montana all honor the deduction, but they arrive at that answer through four distinct mechanisms. For tipped workers choosing where to live or simply trying to understand their state return, those differences matter.
Four different conformity mechanisms
States connect to the federal tax code in different ways. Some start their tax calculation from federal taxable income, inheriting all federal deductions automatically. Others start from federal AGI or their own definition of income, requiring explicit legislative action to adopt new federal deductions. Here is how these four states handle it:
- Colorado: Structural flow-through from federal taxable income (4% flat rate)
- Arizona: its own subtraction, HB 4168 (3% flat rate)
- Iowa: Explicit DOR guidance plus structural flow-through (4% flat rate)
- Montana: Federal taxable income base (5%/6% graduated rates)
Colorado: structural flow-through
Colorado computes state income tax by applying its flat 4% rate directly to federal taxable income. This is the simplest conformity mechanism. Because the OBBBA tips deduction reduces federal taxable income (it is an above-the-line deduction that flows through to Form 1040 Line 15), the reduced figure automatically becomes the Colorado tax base. No separate Colorado legislation was needed, and the Colorado DOR has confirmed the flow-through.
This structural approach means Colorado will automatically adopt any future federal above-the-line deduction that reduces federal taxable income, unless the state legislature explicitly decouples. For tipped workers, the benefit is immediate and requires no special action on the state return.
Arizona: its own subtraction (HB 4168)
Arizona takes a different path. Its return starts from federal adjusted gross income, and the OBBBA tips deduction is taken after AGI, so the federal deduction alone would not reduce Arizona income. Instead, HB 4168 (Laws 2026, Chapter 140, approved June 13, 2026) added an Arizona subtraction for qualified tips deducted under IRC §224, along with overtime (§225) and the senior deduction, retroactive to taxable years beginning after December 31, 2024.
For 2025, the subtraction is claimed on Form 140, page 6, line V. At the state's flat 3% rate, a worker deducting $20,000 in tips saves $500 in Arizona state tax. Arizona's rate is one of the lowest flat rates in the country, but the savings are additive with the federal deduction.
Iowa: explicit DOR guidance + structural
Iowa provides what might be called a "belt and suspenders" answer. The state conforms through two independent mechanisms. First, Iowa's IA 1040 starts from federal taxable income (Line 02 equals federal Form 1040 Line 15), so the OBBBA deduction structurally flows through. Second, the Iowa DOR published explicit guidance confirming that qualified tip income is not subject to Iowa income tax under the OBBBA.
Either mechanism alone would be sufficient, but having both provides the strongest possible confirmation. At Iowa's flat 4% rate, a worker deducting $20,000 in tips saves $760 in Iowa state tax.
Montana: federal taxable income base
Montana, like Colorado, starts from federal taxable income as its computation base. The OBBBA tips deduction reduces federal taxable income, and that reduced figure flows into Montana's tax calculation. However, Montana differs from the other three states in two important ways: it uses a graduated rate structure and applies its own standard deduction and personal exemption on top.
Montana's 2026 brackets are 5% on income up to $21,600 (single) and 6% above that. The state also applies its own standard deduction of $5,540 and a personal exemption of $3,000. Because the tips deduction has already reduced the federal taxable income starting point, the Montana deductions are applied to a smaller base, and the graduated rates determine the actual savings.
Worked example: $20,000 tips in each state
Scenario: A single filer earns $40,000 in base wages and $20,000 in qualified tips during 2026. Total income: $60,000. MAGI is well below the federal phase-out threshold. The worker claims the full $20,000 federal tips deduction on Schedule 1-A.
Federal return (same for all four states):
Federal taxable income before tips deduction: $43,900
Federal taxable income after tips deduction: $23,900
State-level savings from the tips deduction:
| State | Rate | Mechanism | State tax saved |
|---|---|---|---|
| Colorado | 4% flat | Structural flow-through | $880 |
| Arizona | 3% flat | Own subtraction (HB 4168) | $500 |
| Iowa | 4% flat | Explicit DOR + structural | $760 |
| Montana | 5%/6% graduated | Federal taxable income base | $1,071 |
All four states deliver real state-level savings on top of the federal deduction. The dollar amounts vary because of different rates: Arizona's 3% rate produces the smallest per-dollar savings, while Montana's graduated structure (with income potentially in the 6% bracket) produces the largest. Colorado and Iowa fall in between at 4% and 4%, respectively.
Why the mechanism matters
For a tipped worker filing a 2026 return, the practical outcome is the same in all four states: the tips deduction reduces your state tax. But the mechanism matters for durability and predictability.
- Structural flow-through (Colorado, Iowa, Montana) is the most durable. Because the state tax base is defined as federal taxable income, any future federal deduction automatically flows through without new state legislation. The state would need to actively decouple to block a federal provision.
- An explicit state subtraction (Arizona) names the federal deductions it mirrors. It keeps working even though the deductions sit below AGI, but a future federal deduction would need its own Arizona law.
- Explicit DOR guidance (Iowa) provides administrative certainty. Even if there were ambiguity in the structural mechanism, the published DOR guidance eliminates doubt. This is especially valuable during the first filing season after a major federal tax change.
Workers in non-conforming states like New Jersey, Massachusetts, Kentucky, and Minnesota do not receive any state-level benefit from the OBBBA tips deduction. Wisconsin also does not conform after the governor vetoed tips and overtime bills. Michigan and Indiana have since confirmed conformity through their own mechanisms - see our updated conformity tracker for details. The gap between conforming and non-conforming states can add hundreds or thousands of dollars to a tipped worker's annual state tax bill.
For the complete state-by-state breakdown, see our state tips and overtime taxes map. You can also estimate your take-home pay using the Colorado,Arizona,Iowa, or Montana paycheck calculators.