Oklahoma’s fuel tax is $0.16 per gallon on gasoline and $0.13 per gallon on diesel, with additional state assessments pushing the effective rate to roughly $0.19 and $0.16 respectively. Distributors precollect the tax at the terminal, so it’s already built into the price at the pump. You never file or pay it directly unless you used fuel for an exempt purpose, drive an electric or hybrid vehicle, or operate commercial trucks across state lines.
Gasoline and Diesel Rates
The base excise rates under Oklahoma’s Motor Fuel Tax Code are $0.16 per gallon for gasoline and $0.13 per gallon for diesel.1Oklahoma Legal Information System. Oklahoma Code 68-500.4 – Tax Imposed on Gasoline and Diesel Fuel Add in state-level charges like the underground storage tank fee and inspection assessments, and the total comes to roughly $0.19 per gallon of gasoline and $0.16 per gallon of diesel. Those are the figures used in national comparisons, and they place Oklahoma well below the national average.
Because the tax is precollected by licensed suppliers at the terminal rack or point of import, every gallon entering the state’s distribution chain carries the tax before it reaches a station. You don’t see it broken out on the receipt, and you don’t file anything.
Agricultural, CNG, and LNG Rates
Gasoline used exclusively in farm tractors or stationary engines is taxed at $0.0208 per gallon rather than the standard $0.16.1Oklahoma Legal Information System. Oklahoma Code 68-500.4 – Tax Imposed on Gasoline and Diesel Fuel The reduced rate applies only to off-road farm equipment. Pickups, cars, and anything else registered for highway use pay the full rate.
Compressed natural gas is taxed at $0.05 per gasoline gallon equivalent (GGE), and liquefied natural gas at $0.05 per diesel gallon equivalent (DGE).2New York Codes, Rules and Regulations. Oklahoma Code 68 500.4 – Levy of Tax One GGE equals 5.66 pounds of CNG, and one DGE equals roughly 6.06 pounds of LNG.
Those rates are temporary. Both expire on December 31, 2026. Starting January 1, 2027, CNG and LNG will be taxed at the diesel rate, measured in their respective gallon equivalents. If you run a fleet on natural gas, plan for the increase.
Electric and Hybrid Vehicle Fees
EVs don’t burn taxable fuel, so Oklahoma collects road-funding revenue through annual registration fees that scale by vehicle weight. The fees are charged on top of your normal registration.3Alternative Fuels Data Center. Electric Vehicle and Plug-In Hybrid Electric Vehicle Fee
- 6,000 lbs. or below: $110 for fully electric, $82 for plug-in hybrid
- 6,001 to 10,000 lbs.: $158 EV, $118 plug-in hybrid
- 10,001 to 26,500 lbs.: $363 EV, $272 plug-in hybrid
- Over 26,501 lbs.: $2,250 EV, $1,687 plug-in hybrid
For a typical passenger EV, the $110 annual fee roughly approximates what a comparable gasoline car would pay in fuel tax over a year of average driving.
Federal Tax at the Pump
What you pay at the pump also includes federal excise tax. The federal rate is 18.4 cents per gallon for gasoline and 24.4 cents per gallon for diesel.4GovInfo. 26 USC 4081 – Imposition of Tax Of each, 0.1 cent funds the Leaking Underground Storage Tank Trust Fund; the rest goes to the Highway Trust Fund.
Combined with the state portion, a gallon of gasoline in Oklahoma carries roughly $0.37 in total fuel taxes, and a gallon of diesel about $0.40. Both totals remain among the lower in the country.
Who’s Exempt from Oklahoma Fuel Tax
A long list of fuel uses are exempt from the standard excise. The categories most people encounter:
- Fuel for farm tractors and stationary engines used exclusively in farming (either exempt or taxed at the reduced agricultural rate)
- Fuel sold to federal agencies, county and city vehicles, public school buses, and FFA or 4-H trucks transporting students
- Vehicles operated by state-certified volunteer fire departments, rural electric cooperatives, rural water and sewer districts, and rural ambulance service districts
- Motor fuel sold within Indian country by a federally recognized tribe to a tribal member for use in that member’s vehicle
- Fuel exported from Oklahoma with terminal-issued destination state shipping papers
The full statutory list includes narrower categories as well.5Justia. Oklahoma Code 68-500.10 – Exemptions from Motor Fuels Tax Each exemption carries its own procedural requirements, and most demand proof that the fuel was not used on public highways.
Claiming a Refund
If you bought fuel with the full tax included and then used it for an exempt purpose, file Oklahoma Tax Commission Form 130 (Application for Refund of Motor Fuel Tax for Gasoline and Undyed Diesel). The form asks for total gallons purchased, gallons used for the exempt purpose, and your identifying tax information.
You can submit through the Oklahoma Taxpayer Access Point (OkTAP) portal or mail a paper copy to the Tax Commission in Oklahoma City.6Oklahoma Tax Commission. Help Center: OkTAP For direct deposit, complete Form ARDD-100 as well.
Record-keeping decides most refund claims. Oklahoma presumes all fuel is used for taxable highway purposes unless you prove otherwise. At minimum, keep original purchase invoices showing gallons bought, tax paid, and seller information, plus usage logs separating exempt equipment from highway vehicles. If a single storage tank serves both, you need metered withdrawals or a physical inventory system that distinguishes them.
If the fuel went to off-highway farming, construction machinery, commercial fishing boats, or certain buses, you may also qualify for the federal fuel tax credit on IRS Form 4136, filed with your income tax return.7Internal Revenue Service. Fuel Tax Credit The federal credit does not apply to personal-use vehicles, commuter vehicles, or anything registered for highway driving.
IFTA for Interstate Truckers
If you run commercial trucks across state lines, Oklahoma’s per-gallon tax is only part of what you owe. The International Fuel Tax Agreement lets you report and pay fuel taxes to every state you drive through using one quarterly return filed with your base state.
You need an IFTA license if your vehicles travel in two or more member jurisdictions and meet any of these thresholds:
- Two axles with a gross vehicle weight over 26,000 pounds
- Three or more axles regardless of weight
- Combination vehicles over 26,000 pounds combined weight
Oklahoma handles IFTA registration through the Oklahoma Corporation Commission’s Transportation Division.8Oklahoma Corporation Commission. IFTA Each quarter, you report total miles driven and fuel purchased in every jurisdiction. The return calculates whether you owe additional tax to states where you burned more fuel than you bought, or get a credit from them. If you only occasionally cross state lines, you can skip IFTA and buy a 120-hour fuel permit for each trip instead.
Quarterly returns are due April 30, July 31, October 31, and January 31. When a due date lands on a weekend or holiday, it shifts to the next business day.
Penalties
Selling or delivering motor fuel without paying the required taxes is a misdemeanor carrying a fine of up to $1,000, up to one year in county jail, or both.9New York Codes, Rules and Regulations. Oklahoma Code 68 500.48 – Sale or Delivery of Motor Fuel Without Payment of Taxes
Operating a fuel transport truck on Oklahoma highways without proper shipping documentation is a separate misdemeanor, punishable by up to $1,000 in fines and up to six months in jail. The Tax Commission can seize and dispose of any motor fuel found without the required paperwork.10New York Codes, Rules and Regulations. Oklahoma Code 68-500.49 – Operation of Transport Truck Without Shipping Paper Prohibited Diesel transport loads must carry shipping papers clearly marked “Dyed Diesel Fuel, Nontaxable Use Only, Penalty for Taxable Use” for any untaxed portion.
Using dyed (untaxed) diesel on public highways triggers a federal IRS penalty of $1,000 or $10 per gallon, whichever is greater, with escalating fines for repeat offenders. Enforcement agents conduct random roadside fuel sampling, and the same infraction can draw both federal and state penalties.