Illinois Gas Tax Calculator
2026Illinois charges 49.4¢ a gallon in state tax on gasoline and 56.9¢ on diesel in 2026, on top of the federal 18.4¢ and 24.4¢: 67.8¢ and 81.3¢ a gallon in all. Estimate your fuel costs.
By Konstantin Iakovlev · Updated October 19, 2026 · Methodology
Fuel Needed
1.0 gal
Trip Cost
$4.33
Annual Cost
$1,125.80
Fuel Cost Breakdown
| Total Distance | 30.0 miles |
| Fuel Needed | 1.00 gallons |
| One-Way Cost | $4.33 |
| Trip Cost | $4.33 |
| Weekly Cost | $21.65 |
| Monthly Cost | $93.82 |
| Annual Cost | $1,125.80 |
Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.
Illinois Gas Tax Overview
Illinois’s state tax on gasoline is 49.4¢ a gallon and 56.9¢ on diesel, the rate in force since July 1, 2025. That is the 5th-highest state gasoline tax of the 50 states and DC. Normally adjusted for inflation each July 1; the July 2026 increase is suspended through December 31, 2026.
With the federal 18.4¢, a gallon of gasoline carries 67.8¢ of per-gallon tax, so a 15-gallon fill-up includes about $10.17 of fuel tax whatever the pump price. The 6.25% state sales tax plus local sales taxes also apply to fuel. They are prepaid at 21¢ a gallon on gasoline below E15 and diesel below B10 for July–December 2026 (19¢ on E15, 17¢ on mid-range ethanol blends). Several counties add their own per-gallon tax (DuPage 10¢, McHenry 8.7¢, Kane 8¢, Will 5.1¢, Lake 4.9¢), and some other counties and many cities levy local fuel taxes too.
The rate is due to be reset on January 1, 2027; the new figure is not published yet.
Illinois Fuel Taxes (2026)
| State Gasoline Tax | 49.4¢/gal |
| State Diesel Tax | 56.9¢/gal |
| Federal Excise Tax | 18.4¢ gasoline / 24.4¢ diesel |
| Total per Gallon | 67.8¢ gasoline / 81.3¢ diesel |
| Sales and Other Taxes on Fuel | The 6.25% state sales tax plus local sales taxes also apply to fuel. They are prepaid at 21¢ a gallon on gasoline below E15 and diesel below B10 for July–December 2026 (19¢ on E15, 17¢ on mid-range ethanol blends). |
| How the State Rate Is Built | Gasoline: 48.3¢ motor fuel tax + 0.3¢ underground storage tank tax + 0.8¢ environmental impact fee. Diesel: 55.8¢ motor fuel tax + the same two fees. |
| Next Change | January 1, 2027: new rate not yet published |