Taxes explained
Colorado fuel taxes
Fixed duties and percentage taxes work differently. These records preserve effective dates and unresolved checks.
| Tax / fuel | Rate | Effective from | Through | Status and source |
|---|---|---|---|---|
| Excise Fixed gasoline | USD 0.1283/L | 2026-07-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0600/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
| Excise Fixed diesel | USD 0.1587/L | 2026-07-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0600/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
| Excise Fixed gasoline | USD 0.1257/L | 2026-01-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0500/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
| Excise Fixed diesel | USD 0.1561/L | 2026-01-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0500/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
| Excise Fixed gasoline | USD 0.1257/L | 2025-07-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0500/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
| Excise Fixed diesel | USD 0.1561/L | 2025-07-01 | Open / check source | Source verified Bridge and Tunnel Impact (BTI) Fee: $0.0700/gal, diesel only. Environmental Response Surcharge (ERS): $0.0125/gal, gasoline and diesel. Fuel Impact Reduction Fee (FIRF): $0.006125/gal, gasoline and diesel. Perfluoroalkyl and Polyfluoroalkyl Substances Fee (PFAS): $0.003125/gal, gasoline and diesel. Road Usage Fee (RUF): $0.0500/gal, gasoline and diesel. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included. |
Common questions
Does a percentage tax stay fixed in cents per litre?
No. VAT, GST and sales taxes vary with their taxable base. For a tax-inclusive price and one rate r, the tax amount is price × r / (1 + r).
Why are some tax records marked unverified?
A published summary can omit a local levy, a tax-base rule or an effective date. Unverified records are not treated as a complete statutory tax stack.