Idaho · 2027 and beyond
Idaho in 2027 and beyond: what is already law, and what is still open
No tax measure on the ballot. Idaho adopted the federal deductions; nothing new is enacted for 2027. What is on the 2026 return, what starts with tax year 2027, and what is scheduled or conditional after that.
By Charles Trautman, EA, editor
Need to Know Tax · written from Idaho State Tax Commission sources and the unofficial November 3 election returns, November 12, 2026 · not yet reviewed by an Idaho practitioner
No tax measure on the ballot. Idaho adopted the federal deductions; nothing new is enacted for 2027. This page keeps apart three things that get mixed together in the news: what is on the 2026 return you file in early 2027, what begins with tax year 2027, and what is scheduled, conditional or still undecided after that. Election figures are the unofficial November 3, 2026 returns and are not final until the state certifies them.
What the voters decided on November 3, 2026
No statewide tax measure was on the November 3, 2026 ballot in Idaho. Nothing voted on that day changes a Idaho return.
This return, next year, and later
| When | What applies |
|---|---|
| The 2026 return, filed in early 2027 | The flat rate is 5.3%. |
| HB 559 conformed Idaho to the federal code, so the federal deductions for tips, overtime, car-loan interest and seniors reduce Idaho income too. | |
| The $205 child tax credit ended with tax year 2026. | |
| The grocery credit is $155 a person. | |
| Starting with tax year 2027 | The property tax reduction (circuit breaker) income limit is $40,030 of 2026 income for the 2027 program; the deferral limit is $63,400. |
| Any federal change made during 2026 waits for the 2027 session’s conformity bill. | |
| 2028 and later, or conditional | No rate change is enacted. |
Items under 2027 and later do not change the 2026 return. They matter for 2027 withholding, estimated payments and planning. The detail behind each line is in the other Idaho articles.
The 2025 federal law and the Idaho return
Idaho conforms to the Internal Revenue Code as of a fixed date and moves the date by statute each session. HB 559, signed February 10, 2026, moved it to January 1, 2026, retroactive to the start of 2025. Bonus depreciation is not followed.
That is the reason a change on the federal return, such as the deductions for tips, overtime and people 65 and older, may or may not show up on the Idaho return. The federal side is in The new deductions for tips, overtime and seniors.
What to watch
The 2027 conformity bill, usually among the first signed each session. When something on this page changes, the change is logged on the updates page with its date.
What to bring
- Your 2026 federal and Idaho returns, once filed, to set 2027 withholding and estimated payments against them
- Your last pay stub of 2026 and the first of 2027, to see whether withholding changed
- Any notice from the state about a 2027 rate, credit or filing change
Questions people ask
Does anything here change the Idaho return I file in early 2027?
Only what is listed under the 2026 return. Everything listed under 2027 or later affects withholding, estimated payments and planning, not the return for 2026.
How will I know if this page changes?
Every change is logged on the updates page with its date and the article it affects. State legislatures meet in early 2027 and some act before the filing deadline.
Idaho, after the election
No tax measure on the ballot. Idaho adopted the federal deductions; nothing new is enacted for 2027.
Written by Charles Trautman, EA, editor · Need to Know Tax, Lone Tree, Colorado
Questions about this article in Idaho are answered by [your practice name] · [your phone] · [your email address]. We’re looking for an EA or CPA in each Idaho city to hold that city’s seat and take this spot — is that you?
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These Idaho pages were written by the editor from the Idaho State Tax Commission’s own publications, and they need an Idaho practitioner’s eye. One enrolled agent or CPA in each Idaho city holds that city’s seat: reads these pages before the filing season and is credited as a reviewer, is named on every page of their city’s edition, and answers its readers’ questions. $1,000 for the 2026 season, the charter price. Take your city’s seat (a two-minute form and a card), tell us you’re interested, write to editor@needtoknowtax.com, or read how it works.
Sources and where to check
- Idaho State Tax Commission: Update on filing 2025 Idaho income taxes now that conformity is law (February 17, 2026)
- Idaho State Tax Commission: More guidance on conformity deductions (February 20, 2026)
- Idaho State Tax Commission: What’s new for 2025 income tax returns (March 11, 2026)
- Idaho State Tax Commission: Withholding tables updated for 2026; child tax credit has ended (July 31, 2026)
- Idaho State Tax Commission: Need an extension to file your Idaho income tax return? (April 6, 2026)
- Idaho State Tax Commission: Parental Choice Tax Credit application period to reopen (May 19, 2026)
- Idaho State Tax Commission: Claim your food tax credit even if you don’t earn enough to file (April 1, 2026)
- Idaho State Tax Commission: Individual income tax forms