What is the hawaii gas tax 2025 — 16¢/gallon?
In short
Hawaii's state gas tax is 16¢ per gallon in 2025 — about 5% of a $3.50 gallon of gas. A typical driver doing 15,000 miles/year at 28 MPG buys ~536 gallons and pays roughly $86/year in Hawaii state gas tax alone (plus the federal 18.4¢/gal).
This page shows Hawaii's 2025 state gas tax rate and calculates how much you pay in state fuel tax based on your annual mileage and fuel economy. The figure does not include the federal excise tax (18.4¢/gallon) or any local county/city fuel taxes.
How to use this calculator
- 1The Hawaii state gas tax of 16¢/gallon is already filled in.
- 2Enter your annual miles driven.
- 3Enter your vehicle's fuel economy (MPG).
- 4See your annual gallons used and state gas tax paid.
The formula
- cents/gallon
- — Hawaii state excise tax per gallon: 16¢
- annual gallons
- — Annual miles ÷ fuel economy (MPG)
- state tax paid
- — Annual gallons × state cents per gallon ÷ 100
- federal tax
- — 18.4¢/gallon federal excise — same in every state
Worked example
The scenario
15,000 miles/year, 28 MPG, Hawaii state gas tax 16¢/gallon.
The result
Annual gallons = 15,000 ÷ 28 = 536 gallons. State gas tax = 536 × $0.1600 = $86/year. Total gas cost at $3.50/gal = $1875/year (of which $86 is Hawaii tax and $99 is federal tax).
Common use cases
- Understanding how much of your gas bill goes to Hawaii fuel taxes
- Comparing gas tax costs between states before relocating
- Estimating annual fuel costs for a new vehicle purchase
- Advocacy or understanding of transportation funding
Limitations & assumptions
- The federal gas tax (18.4¢/gallon) is not included — it applies in addition to the state tax.
- Local county or city gas taxes in Hawaii are not included; some areas charge additional surcharges.
- Actual pump price varies by station, location, and crude oil markets — the tax is fixed but the retail price fluctuates.
- Diesel, flex-fuel, and other fuel types may have different tax rates.
Frequently asked questions
Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.