Ada County sales tax rate, Idaho
Quick answer
Combined sales tax in Ada County runs 6% across the cities we cover, on top of Idaho's 6% state rate. The county share is a separate line from any city or special-district increment, which is why two addresses in the same county can pay different totals.
Cities in Ada County
County share shown separately from the city and district layers.
| City | State | County | City + districts | Combined |
|---|---|---|---|---|
| Boise | 6% | 0% | 0% | 6% |
Source: Idaho State Tax Commission · rates as published for 2026