IFTA Louisiana Requirements: Filing, Records, and Penalties

If you’re a Louisiana-based motor carrier running qualified trucks into other states or Canadian provinces, Louisiana’s IFTA requirements come down to four things: get an International Fuel Tax Agreement license and decals from the Louisiana Department of Revenue, file a consolidated quarterly fuel tax return, pay what you owe each jurisdiction based on miles driven and fuel purchased, and keep four years of supporting records. Louisiana taxes motor fuels at $0.20 per gallon, but your actual liability shifts jurisdiction by jurisdiction depending on where the miles and gallons land.¹

Who Needs a Louisiana IFTA License

You need one if you operate a qualified motor vehicle in two or more IFTA member jurisdictions. IFTA covers all 48 contiguous U.S. states and 10 Canadian provinces. A vehicle is qualified if it has two axles and a gross or registered gross weight over 26,000 pounds, three or more axles regardless of weight, or is used in a combination whose total weight exceeds 26,000 pounds.²

Recreational vehicles are excluded even when they exceed those weight thresholds. Motorhomes, pickups with attached campers, and buses used exclusively for personal pleasure fall outside IFTA.

If every mile you drive stays inside Louisiana, IFTA does not apply to you. Carriers who don’t qualify for IFTA or choose not to join have to follow each jurisdiction’s own fuel tax registration and reporting rules, which is why anyone crossing state lines regularly signs up.³

License, Decals, and Fees

Louisiana-based carriers apply through the Louisiana Department of Revenue. Once approved, LDR issues a license and two decals for each qualified vehicle. Initial decals cost $1.00 per decal. Additional sets during the license year and renewal sets cost $2.00 per set.³

Decals go on the exterior of both sides of the cab so they’re visible during roadside inspections. Current-year decals are valid January 1 through December 31. You can display next-year decals starting November 1, and the current year’s decals must be displayed by March 1.⁴

Trip Permits for Occasional Crossings

If a vehicle isn’t IFTA-licensed and only enters Louisiana on a one-time or occasional basis, you can buy a temporary trip permit instead. Louisiana trip permits are valid for 48 hours and cost $50.00. You can get them through wire service companies, DOTD Weight Enforcement Division Port of Entry scales, or the Office of Motor Vehicles. This is a stopgap. For any truck making regular interstate trips, the permit route quickly becomes more expensive than IFTA registration.

Quarterly Returns and Deadlines

Louisiana carriers file quarterly using Form R-5406. The return consolidates fuel purchases and miles traveled across every jurisdiction into a single report, and LDR calculates what you owe each state or province (or what credit you’re due) based on fuel consumed versus fuel purchased in each. You can file electronically through Louisiana’s online system, LaTAP.³

Returns are due the last day of the month following the end of each quarter. When that date falls on a weekend or holiday, the deadline shifts to the next business day. For 2026:

First quarter (January–March): April 30, 2026
Second quarter (April–June): July 31, 2026
Third quarter (July–September): November 2, 2026 (October 31 falls on a Saturday)
Fourth quarter (October–December): February 1, 2027 (January 31 falls on a Sunday)

Records You Have to Keep

IFTA requires carriers to retain operational records for four years after the return due date or filing date, whichever is later, and Louisiana follows that standard.⁵ The core records behind every quarterly filing are:

Trip reports showing origin, destination, route, and beginning and ending odometer readings for each trip.
Fuel purchase receipts with the date, seller name and address, gallons, fuel type, price per gallon, and the vehicle or unit number.
Mileage summaries showing total miles driven in each jurisdiction for the quarter.

The records need to be detailed enough that an auditor could reconstruct your quarterly returns from scratch. Vague or incomplete documentation is where most carriers get into trouble.

ELDs and GPS Data

If you use a vehicle tracking system that records GPS coordinates, it must create a record at least every 10 minutes while the engine is running. Each record needs the date and time, latitude and longitude to at least four decimal places, the odometer reading from the engine control module, and the vehicle identification or unit number. Data must be exportable in spreadsheet formats such as CSV or XLS. Static image formats like PDF or JPEG are not acceptable for audit purposes.

One trap catches carriers off guard: an ELD that satisfies FMCSA hours-of-service rules does not automatically satisfy IFTA record-keeping requirements. There is no official IFTA certification for electronic logging systems, despite what some vendors claim. Verify your device actually captures the required data elements before relying on it for fuel tax reporting.

Penalties, Interest, and License Loss

Under the IFTA framework, the standard penalty for a late quarterly return is $50 or 10 percent of the net tax due, whichever is greater.⁶ Louisiana also applies its own delinquency penalty of 5 percent of the tax due for the first 30 days, with an additional 5 percent for each additional 30-day period, up to a maximum of 25 percent.⁷

Interest accrues on top. The annual rate for 2025 is 11.25 percent, and Louisiana sets a new rate each year.⁸ Interest runs from the original due date until you pay.

Repeated failures to file or pay can lead to suspension or revocation of your IFTA license. Once it’s revoked, you lose the ability to operate legally across state lines without buying a trip permit for every jurisdiction you enter.

Roadside Enforcement

Officers check for current IFTA credentials at weigh stations and roadside inspections. If your driver can’t produce a copy of the IFTA license in the cab, or the vehicle doesn’t display valid decals, the consequences can include a mandatory trip permit purchase, a citation, or both.⁴ Improper use of credentials, such as running decals from a suspended license, can be grounds for permanent revocation.

What Triggers an Audit

The Louisiana Department of Revenue audits carriers to verify that reported fuel use and mileage match actual operations. Audits can be random, but they’re more often triggered by reporting patterns that don’t add up: miles in California and Texas with nothing in between, fuel purchases in states where the truck has no recorded travel, unrealistic miles per gallon on a heavy vehicle, or repeated small discrepancies that suggest a systemic problem. Once auditors find patterns of errors, they can expand the review to cover the full four-year retention period.

Common sources of these errors include ELD signal failures in areas with poor cell coverage, drivers using the wrong fuel card, incorrect unit numbers on fuel receipts, and bulk fuel that isn’t properly reconciled to individual vehicles. The best defense is reconciling fuel against mileage every quarter as you file, not months later when a notice arrives. If a vehicle’s MPG looks unusually high or low, investigate before you file rather than trying to explain the number after the fact.

Contesting an Assessment

If you disagree with an audit finding or a penalty, you can challenge it. The usual path starts with an informal review with LDR. If that doesn’t resolve the dispute, you can escalate to the Louisiana Board of Tax Appeals, which hears state and local tax matters.⁹

Effective challenges usually focus on the underlying data. Records showing that the auditor’s methodology was flawed or that specific calculations were wrong give you a concrete basis for reversal. Procedural arguments also carry weight: inadequate notice of the audit or incorrect penalty calculations can invalidate an assessment. The Board of Tax Appeals can order refunds or credits if it determines you overpaid.¹⁰

1
Louisiana Department of Revenue. What Is the Tax Rate on Gasoline, Diesel and Special Fuels
2
IFTA, Inc. IFTA Qualified Motor Vehicle Definition
3
Louisiana Department of Revenue. IFTA International Fuel Tax Agreement Compliance Manual
4
IFTA, Inc. IFTA Articles of Agreement Manual
5
IFTA, Inc. IFTA Procedures Manual
6
IFTA, Inc. IFTA Procedures Manual
7
Louisiana State Legislature. Louisiana Revised Statutes Title 47 – 1602 Penalty for Failure to Make Timely Return
8
Louisiana Department of Revenue. RIB 25-001 Interest Rate Collected on Unpaid Taxes
9
Louisiana Board of Tax Appeals. Louisiana Board of Tax Appeals
10
Justia Law. Louisiana Code 47:337.81.1 – Board of Tax Appeals; Finding of Overpayment Upon Appeal From Assessment