Idaho corporate tax rate history
The Idaho State Tax Commission's own history of the flat corporate income tax rate on Idaho taxable income, tax years 2001-2025.
Figures
Source: Idaho State Tax Commission, Business Income Tax Rates. Data period 2025. Published .
| Measure | Value | Period |
|---|---|---|
| Corporate income tax rate2025 | 5.3% | 2025 |
Pages built on this dataset
Publisher
- Organization
- Idaho State Tax Commission
- Publisher’s dataset
- Business Income Tax Rates
- File or API used
- https://tax.idaho.gov/taxes/income-tax/business-income/online-guide/#BITRates
- Methodology
- https://tax.idaho.gov/taxes/income-tax/business-income/online-guide/#BITRates
Coverage
- Geography
- Idaho (statewide; the rate does not vary by locality)
- Time coverage
- 2001-2025
- Update frequency
- Annual, after each legislative session that changes the rate; the Commission adds each new tax year's rate to this same page.
- Published
- August 2025
- Retrieved
- September 13, 2026
- License of the records
- Public domain. State of Idaho government work.
- Rows
- 25 observations, 2001-2025
Measures
| Measure | What it measures | Unit |
|---|---|---|
| Corporate income tax rate | The flat corporate income tax rate on Idaho taxable income for the tax year. | percent |
Caveats
- Idaho's corporate income tax is a single flat rate on Idaho taxable income; there are no brackets.
- The corporation franchise tax carries the same rate as the corporate income tax; a corporation owes one or the other, never both.
- The Commission's own table states one rate across each of three multi-year spans (2018 through 2020, 2012 through 2017, and 2001 through 2011); this dataset stores that rate for every year in the span, since the Commission's table says the rate held constant across it.
How to cite
Understand Idaho, “Business Income Tax Rates”, compiled from Idaho State Tax Commission, Business Income Tax Rates. Retrieved September 13, 2026. https://understandidaho.com/data/idaho-tax-business-rates/.
Cite Idaho State Tax Commission directly for the figures themselves.
This page was last updated .