Idaho State Tax Commission

Idaho State Tax Commission

IFTA Licensees

For more information on trucking in Idaho, see and IFTA, Inc.

You can save time and postage by e-filing your IFTA returns and payments. You can also apply for your IFTA license, complete your annual license renewal, and reorder decals — all online.

IFTA Terms Defined

Auxiliary Engine
An engine fueled by the main supply tank of a vehicle, but separate from the main engine that propels the vehicle. Auxiliary engines are used to operate equipment such as refrigeration units and carpet cleaning units.
Base Jurisdiction
The jurisdiction where qualified motor vehicles are based for vehicle registration purposes, where the operational control and records of a licensee's qualified motor vehicles are maintained or can be made available, and where some miles are traveled by qualified motor vehicles in the IFTA fleet.
Bulk Fuel
Fuel kept in a tank that will be redistributed and doesn't directly supply an engine. This includes fuel placed in mobile fuel tanks used for fueling other pieces of equipment and fuel kept in a small tank in the bed of a pickup truck, regardless of the size of the container. Bulk storage fuel can be either gasoline, ethanol blended fuel, biodiesel, biodiesel blended fuel, or diesel, dye-added or undyed.
Diesel Fuel, Dye-Added
Fuel that can be used for purposes other than operating a motor vehicle on public highways. The fuel is dyed red according to U.S. Environmental Protection Agency and Internal Revenue Service regulations. In Idaho, special fuels tax isn't charged on dye-added diesel fuel. The fuel becomes subject to that tax if it's used for a taxable purpose. Dye-added diesel fuel can be subject to sales and use tax.
Federal and state law prohibits the use of dye-added diesel fuel in most licensed vehicles and in unlicensed vehicles equipped for highway use. This includes vehicles that never leave private property or that operate entirely on job sites or Forest Service roads. Even occasional use of dye-added fuel will contaminate a fuel tank and is against the law.
Diesel Fuel, Undyed
Fuel with no dye added which can be used for any purpose, including operating or propelling a motor vehicle on public highways. In Idaho, as in most other jurisdictions except Oregon, tax is included in the purchase price of undyed diesel fuel.
A roadway open for use by the public that is maintained by the state of Idaho or its political subdivisions (county, city, agency, district) or the federal government. Highways can be constructed of concrete, asphalt, gravel, composition, dirt, or other materials.
IFTA Fleet Consolidation
The approved consolidation of IFTA fleets that are based in two or more jurisdictions. The IFTA commissioners of two or more affected jurisdictions can allow a person to consolidate several IFTA fleets that would otherwise be licensed in two or more jurisdictions.
IFTA-Qualified Vehicles
Vehicles included in an IFTA fleet that usually travel in more than one jurisdiction. For IFTA fuels use tax reporting, a qualified motor vehicle is one designed to transport persons or property and is a power unit with two axles and a gross vehicle weight or registered gross vehicle weight of more than 26,000 pounds, or power unit with three or more axles regardless of weight, or tractor-trailer combination, with a combined gross vehicle weight or registered gross vehicle weight of more than 26,000 pounds.
A vehicle that doesn't meet the definition of an IFTA-qualified motor vehicle must not be included in an IFTA fleet, display an IFTA decal, or be included in the data on your IFTA fuel tax return. Recreational vehicles, such as motor homes, pickup trucks with attached campers, and buses that are used exclusively for personal pleasure, don't qualify for the IFTA program.
Individual Vehicle Mileage and Fuel Report (IVMR)
A document used to capture information on the day-to-day operations of each truck in an IFTA fleet. This usually is a trip envelope filled out by the driver.
International Registration Plan (IRP)
A registration reciprocity agreement among member states and Canadian provinces providing that license fees be paid based on total distance operated in all jurisdictions.
A jurisdiction is a state of the United States or District of Columbia; province or territory of Canada; or state, territory, or agency of Mexico included as a participant of IFTA.
Miles Per Gallon (MPG)
Total gallons of fuel consumed divided into total miles traveled. For IFTA returns, this includes all fuel used by the IFTA fleet vehicles, regardless of where or how the fuel was acquired. Total miles are miles traveled everywhere, including off-highway miles and miles driven under a temporary permit for fuels tax.
Nontaxable Fuel
Fuel that's used to operate unlicensed equipment and isn't drawn from the supply tank of a motor vehicle. This fuel can't be included on any part of the IFTA return. Although this fuel isn't subject to the special fuels tax, it may be subject to sales and use tax in Idaho.
Nontaxable Mileage
A vehicle's mileage that isn't subject to the jurisdiction's motor fuel taxes. Each jurisdiction has its own definition of nontaxable mileage. In Idaho, nontaxable mileage is when the vehicle is either operating under a temporary fuels tax permit or driven off-highway.
Off-Highway Miles (Idaho only)
Any miles not driven on a highway.
Over-The-Road (OTR) Fuel Purchases
Fuel placed directly into the main supply tank of a vehicle from the seller's tank.
Penalty and Interest
Charges are added when a licensee files late or doesn't pay all of the tax due by the due date of the return. Penalty is calculated at 10% of the tax due or $50, whichever is greater. If your return isn't postmarked by the due date, interest is due for each month the return is late (one day late in a month makes the return late for the entire month). Interest is calculated for each jurisdiction that has tax due; it is not credited if a jurisdiction is overpaid. Please refer to the Form 3150 instructions for the applicable interest rate.
Partial payments are credited first to any interest, second to tax, and then to the penalty. Example: A return is due April 30, 2008, and the tax due is $1,000. The return isn't filed until June 7, 2008. The penalty is $100. Interest is $20 (one day or more into the month is considered a full month). The total due is $1,120. If the payment is $1,000 it would be applied as follows: Interest: $20 + Tax: $980 + Balance due: $120 ($20 tax plus the $100 penalty). Interest continues to apply to the unpaid tax balance of $20 until it is paid in full.
Power Take-Off (PTO) Equipment
Vehicle-mounted equipment powered by the main engine that also propels a motor vehicle. Examples of PTO equipment are trash compactors, concrete mixers, sewage pumps, and conveyors or other loading/offloading devices on vehicles.
Special Fuels
Includes diesel, biodiesel, biodiesel blends, propane, and natural gas.
Statute of Limitations
The time limit during which either the licensee or the jurisdiction can change the information reported on an original return and claim additional tax due or a refund. In Idaho, the statute of limitations is three years from the due date of the return, or the date it was filed, whichever is later.
Tax-Paid Gallons
Gallons of fuel that have a jurisdiction's fuels tax included in the purchase price, including fuel bought at retail stations or delivered in bulk. When motor fuels are purchased from an Indian-owned retail outlet in Idaho after December 1, 2007, the purchase price may not include the Idaho motor fuels tax and may not qualify as an Idaho tax-paid purchase, unless authorized in an agreement between the state and a specific tribe (Idaho Code sections 63-2444 or 67-4002.) Read about Idaho Fuel Purchased on Indian Reservations or contact us.
Temporary Permit
A permit that allows conditional travel in a jurisdiction. A temporary permit can be purchased at a port of entry or from an authorized permit agent on a trip-by-trip basis. A temporary permit can include fees for registration, fuels tax, overweight situations and other elements, or any combination of these. A temporary permit can expire when you leave a jurisdiction or at the end of a specified time period.

Reference: Idaho Code Chapter 24: Fuels Tax .

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Last updated Aug. 12, 2015