Montana IFTA fuel tax rates — 3Q2026
| Fuel | Rate (USD/gal) |
|---|---|
| Diesel | $0.2975 |
| Propane | $0.0518 |
| CNG | $0.0700 |
| Biodiesel | $0.2975 |
The IFTA matrix attaches footnote #9 to Montana. Read them on the official matrix before filing.
Estimate what you owe: IFTA calculator.
Source: IFTA, Inc. 3Q2026 tax matrix, retrieved 2026-10-27.