2026 IFTA Tax Rates by State: Diesel, Gasoline, and Surcharges

Using the wrong fuel tax rate on your IFTA return is one of the fastest ways to trigger an audit adjustment. If you underpay, you owe back taxes plus interest. If you overpay, that money sits with the state until you file an amendment. Either way, you lose.

This guide provides the complete 2026 IFTA tax rate tables for diesel, gasoline, and surcharges across all 48 contiguous states and 10 Canadian provinces. Rates are sourced from the official IFTA Inc. tax rate matrix. Bookmark it and reference it every time you prepare a quarterly return.

How IFTA Tax Rates Work

Every IFTA member jurisdiction sets its own per-gallon fuel tax rate. When you file your quarterly return, you calculate how many gallons you consumed in each state by dividing total miles driven by your fleet's average MPG. That consumption figure is multiplied by the state's tax rate to determine your gross tax liability.

You then receive credit for fuel taxes you already paid at the pump in each jurisdiction. The difference is what you owe — or what's refunded to you.

The per-jurisdiction formula:

Net Tax = (Miles in State / Fleet MPG x State Tax Rate) - Fuel Tax Paid at Pump in State

According to IFTA Inc., the administering body of the International Fuel Tax Agreement, each jurisdiction independently sets and publishes its rates. IFTA Inc. compiles these into a master rate table that is updated before each quarter begins.

Diesel vs. Gasoline vs. Surcharge Rates

Most carriers focus on diesel rates because the vast majority of CMVs run on diesel. However, IFTA covers all qualified motor vehicles regardless of fuel type. If your fleet includes gasoline-powered vehicles that meet IFTA qualifications (two axles and gross vehicle weight over 26,000 pounds, or three or more axles regardless of weight), you need the gasoline rates too.

Some states also impose a surcharge — an additional per-gallon tax on top of the base rate. Surcharges are reported separately on your IFTA return (Schedule 2) and must be calculated independently from the base tax (Schedule 1). When a surcharge applies, you calculate it the same way as the base tax but using the surcharge rate instead.

2026 IFTA Diesel Tax Rates by State

Below are the Q1 2026 diesel fuel tax rates per gallon for all 48 contiguous US states, sourced from the official IFTA Inc. tax rate matrix. Rates may be updated quarterly by individual jurisdictions. Always confirm rates on the IFTA Inc. website before filing.

*Oregon uses a weight-mile tax for trucks instead of a per-gallon fuel tax. Oregon does not have an IFTA diesel rate. Carriers operating in Oregon must obtain a separate Oregon weight-mile tax account.

2026 IFTA Gasoline Tax Rates by State

Gasoline rates differ from diesel rates in most states. If you operate any IFTA-qualified vehicles that run on gasoline, use the table below. Some states do not publish a separate IFTA gasoline rate — these are marked N/A.

States With Surcharges

Three states impose an additional surcharge on top of the base IFTA diesel tax rate. Surcharges are reported on a separate schedule (Schedule 2) of your IFTA return and must be calculated independently from the base tax. If your routes pass through any of these states, failing to account for surcharges will result in an underpayment.

Warning: Indiana's surcharge is particularly significant at $0.6100/gallon — the same as its base diesel rate. This means Indiana's effective diesel cost is $1.2200/gallon when you combine the base tax and surcharge, making it the most expensive IFTA state overall. Surcharge rates can change quarterly, so always verify before filing.

Canadian Province IFTA Rates (Diesel)

All 10 Canadian provinces participate in IFTA. Canadian rates are expressed in dollars per liter rather than per gallon. If you operate cross-border routes, you must use the correct unit — do not convert liters to gallons when reporting Canadian jurisdiction data on your return.

Top 5 Highest Diesel Rate States

If your routes pass through these jurisdictions regularly, precision in mileage tracking is critical. A 100-mile error in California costs far more than the same error in Oklahoma.

1. California — $0.9710/gallon
2. Illinois — $0.7490/gallon
3. Pennsylvania — $0.7410/gallon
4. Indiana — $0.6100/gallon (plus $0.6100 surcharge = $1.2200 effective total)
5. Washington — $0.5840/gallon

Warning: When you factor in Indiana's surcharge, the state's effective diesel rate of $1.2200/gallon is actually the highest in the country — exceeding even California's base rate. Always include surcharges in your cost calculations.

Top 5 Lowest Diesel Rate States

1. Oklahoma — $0.1900/gallon
2. Louisiana & Texas — $0.2000/gallon (tied)
3. Mississippi & New Mexico — $0.2100/gallon (tied)
4. Delaware & Kentucky — $0.2200/gallon (tied)
5. New Hampshire — $0.2220/gallon

Carriers running primarily through the South and Southwest tend to have lower overall IFTA liabilities. However, purchasing fuel in low-rate states doesn't reduce your tax obligation — your tax is based on miles driven in each jurisdiction, not where you buy fuel. Where you fuel only affects your credits.

How Rates Change Quarterly

IFTA rates can change at the start of any calendar quarter. According to IFTA Inc., most states update rates on January 1 and July 1, though some states adjust every quarter. A handful of states — particularly those with variable-rate fuel taxes indexed to wholesale prices — may change rates every single quarter.

The official IFTA Inc. tax rate matrix is published before each quarter begins. Your base jurisdiction also distributes updated rate tables to IFTA licensees. When filing, you must use the rates that were in effect during the quarter you're reporting — not the rates in effect when you sit down to file.

For example, if you're filing your Q1 2026 return in April 2026, use the Q1 2026 rates even if Q2 2026 rates have already been published.

How to Use These Rates in Your Calculation

To calculate your IFTA liability for any single jurisdiction using these rate tables:

1. Total the miles you drove in that state during the quarter
2. Divide by your fleet's average MPG to get gallons consumed
3. Multiply gallons consumed by the appropriate tax rate from the table above (diesel or gasoline)
4. If the state has a surcharge, repeat the calculation using the surcharge rate
5. Subtract the fuel tax you already paid at the pump in that state (shown on your fuel receipts)
6. The result is your net tax owed (positive) or credit due (negative) for that jurisdiction

Repeat for every state where you drove or purchased fuel during the quarter. Sum the results to get your total IFTA liability or refund.

Or skip the manual math — use the free IFTA calculator at FleetCollect to plug in your miles and fuel data and get your return calculated automatically with the correct rates applied.

Frequently Asked Questions

How often do IFTA rates change?

IFTA rates can change at the start of any quarter (January 1, April 1, July 1, or October 1). Most states update rates semi-annually, but some adjust quarterly. IFTA Inc. publishes the official rate matrix before each quarter begins, giving carriers time to update their calculations. Always verify rates before filing — using a rate from a previous quarter is a common audit flag.

Where can I find the official IFTA rates?

The authoritative source is the IFTA Inc. website, which publishes the complete tax rate matrix for all member jurisdictions before each quarter. Your base jurisdiction's department of revenue or motor carrier division also distributes rate updates. Many IFTA filing software programs and calculators pull rates directly from IFTA Inc.'s published tables.

Do Canadian provinces have different rates?

Yes. All 10 Canadian provinces are IFTA members and set their own fuel tax rates independently. Canadian rates are expressed per liter rather than per gallon. When filing your IFTA return, Canadian province data uses liters and kilometers (or miles, depending on your base jurisdiction's form). Do not convert Canadian rates to per-gallon equivalents — use them as published.

Are diesel and gasoline rates the same in every state?

No. Most states tax diesel at a different rate than gasoline. Some states like Louisiana, Mississippi, and North Dakota apply the same rate to both fuel types, but many others differ significantly. You must use the rate that matches your vehicle's fuel type. Using diesel rates for a gasoline-powered IFTA vehicle — or vice versa — will result in incorrect calculations.

What happens if I use the wrong rate on my return?

If an audit reveals you used incorrect rates, your return will be adjusted. You'll owe any underpaid tax plus interest, and potentially penalties depending on the jurisdiction. If you overpaid, you may receive a credit — but it's not automatic, and the process can take months. Using the correct, current rates from the start prevents these issues entirely.