IFTA Tax Rates in Oklahoma (2026)
Oklahoma runs one of the cheapest fuel taxes in America — 19 cents a gallon on gasoline and diesel in the IFTA matrix. Great state to burn miles in; dangerous state to fill up in before crossing into the high-tax Midwest and East. Here are the numbers and the strategy.
By the HaulMath editorial team · Updated $1
Key numbers at a glance
| Jurisdiction | Gasoline ($/gal) | Diesel ($/gal) |
|---|---|---|
| Oklahoma (Q4 2026 IFTA matrix) | 0.1900 | 0.1900 |
| North Dakota (per tax.nd.gov) | 0.2300 | 0.2300 |
| South Carolina (user fee, matrix) | 0.2800 | 0.2800 |
| North Carolina (2026, per NCDOR) | 0.4100 | 0.4100 |
IFTA tax rates in Oklahoma
Oklahoma's IFTA rate is $0.19 per gallon on both gasoline and diesel in the Q4 2026 IFTA Inc. rate matrix. On broad comparison tables the state shows about $0.20 — the Tax Foundation's July 2026 table lists $0.2000, 45th lowest among states, once fee components are folded in — but the number that belongs on your IFTA return is the matrix rate: 19 cents. Rates below are as of Q4 2026 — confirm the current official IFTA matrix before filing, and check ok.gov/tax for any Oklahoma Tax Commission bulletins that affect the quarter.
The state equalized gasoline and diesel at this level after the 2018 increase (gasoline rose from 16 cents, diesel from 13), and the rate has barely moved since. For IFTA purposes that stability is a gift: the Oklahoma line of your return is predictable to the gallon, quarter after quarter.
| Jurisdiction | Gasoline ($/gal) | Diesel ($/gal) |
|---|---|---|
| Oklahoma (Q4 2026 IFTA matrix) | 0.1900 | 0.1900 |
| North Dakota (per tax.nd.gov) | 0.2300 | 0.2300 |
| South Carolina (user fee, matrix) | 0.2800 | 0.2800 |
| North Carolina (2026, per NCDOR) | 0.4100 | 0.4100 |
| Ohio (Q4 2026 matrix, standard rate) | 0.3850 | 0.4700 |
| Pennsylvania (2026, per PA Dept. of Revenue) | 0.5760 | 0.7410 |
| Federal excise (not part of IFTA) | 0.1840 | 0.2440 |
Read the diesel column top to bottom: 19 cents in Oklahoma, 74.1 cents in Pennsylvania. A 150-gallon fill positioned in the wrong state can swing your prepaid credit by $82.65 — that is the entire game IFTA plays with your cash flow, four times a year.
How Oklahoma IFTA affects your filings
The Oklahoma line itself is small. At 6.5 MPG, 1,000 miles on I-40 or I-35 through the state burns about 153.8 gallons, which at 19 cents is roughly $29.22 of Oklahoma tax — often the smallest non-trivial line on a long-haul return. If you fueled in Oklahoma for those miles, you have already paid the tax and the line nets out; Oklahoma miles are close to free from an IFTA standpoint.
The risk lives in the gallons you export. Load up in Oklahoma City at a cheap pump, then run those gallons into Ohio at 47 cents or Pennsylvania at 74.1 cents, and your return charges you the full difference on every burned gallon with almost no credit to offset it. On 150 gallons burned in Pennsylvania, that is $82.65 of tax due that a Pennsylvania fill would have pre-paid. The rule never changes: compare pump price minus that state's tax rate, using the IFTA calculator, and buy your expensive-state miles in the expensive states.
Two Oklahoma-specific notes for 2026. In May 2026 the legislature rewrote parts of the gas tax statutes ahead of possible federal suspension action, and in September the governor paused dyed-diesel enforcement during the price spike — neither changes the 19-cent clear-fuel IFTA rate, but both are reasons to keep an eye on Tax Commission notices through the end of the year. And as always, keep receipts matched to per-state miles: the low rate does not exempt Oklahoma carriers from audit, where four consecutive clean quarters is the standard. Set your fuel surcharge against real after-tax cost, and check every state on the lane with the IFTA rates by state hub.
FAQ
What is the IFTA tax rate in Oklahoma?
19 cents per gallon on gasoline and diesel per the Q4 2026 IFTA matrix. Comparison tables including fees show about 20 cents, but the matrix rate is what goes on the return.
Is Oklahoma's fuel tax the lowest in the country?
It is among the lowest — 45th lowest on the Tax Foundation's July 2026 gasoline ranking, and in the bottom tier of the IFTA matrix for the lower 48.
Why is buying cheap fuel in Oklahoma risky for IFTA?
Cheap-tax fuel pre-pays almost no credit. Burn it in Ohio (47 cents diesel) or Pennsylvania (74.1 cents) and you owe the full gap on the quarterly return.
How much IFTA do 1,000 Oklahoma miles generate?
At 6.5 MPG, about 153.8 gallons — roughly $29.22 at 19 cents per gallon, before pump-tax credits.
Did Oklahoma change any fuel tax rules in 2026?
Statutes were adjusted in May 2026 around possible federal suspension, and dyed-diesel enforcement was paused in September 2026. The 19-cent IFTA rate is unchanged — verify current rules with the Oklahoma Tax Commission.