Q2 IFTA is due May 31. Miss it and you're paying penalties plus interest on top of what you already owe. Here's everything you need to file correctly — including a free calculator that does the math in seconds.
The International Fuel Tax Agreement — IFTA — is the agreement between 48 US states and 10 Canadian provinces that governs how commercial truckers pay fuel taxes when they operate across multiple jurisdictions. Instead of buying fuel permits in every state you enter, you file one quarterly return that distributes your fuel tax owed across every state where you drove miles.
The logic is straightforward: states want fuel tax revenue based on miles driven within their borders, but you might fuel up only in Texas even though you drove through five states. IFTA evens it out. If you burned more fuel in high-tax states than you bought, you pay. If you fueled up in a high-tax state but drove most of your miles in lower-tax states, you get a credit.
You're required to have an IFTA license and file quarterly if your vehicle meets any one of these criteria:
If you only operate within one state and never cross a state line, you're exempt from IFTA — but you'll still owe that state's intrastate fuel tax. Most owner-operators running OTR are in IFTA by default.
One license, 48 states. Your IFTA decal (issued by your base state) is your proof of compliance in every member jurisdiction. Keep the stickers current and on the truck — enforcement officers check them at weigh stations.
IFTA is filed quarterly. Q2 covers April 1 through June 30, but the filing deadline is May 31, 2026 — the last day of the month following the quarter's end. Miss it and the penalties start immediately.
The $50 minimum stings less than the 10% penalty on a large tax bill. If you owe $800 in net IFTA tax and file 30 days late, that's $80 in penalties plus interest. File 90 days late and you're adding penalty on top of compounding interest. It adds up fast, and none of it is deductible as a business expense.
More practically: operating without a valid IFTA license after a suspension means you need a trip permit for every state you enter. At $50–$150 per permit per state, one interstate run can cost you $300–$600 in permits. File on time. It's not complicated — just a calendar problem for most owner-operators.
Q1 2026 was due January 31. If you missed it, you're already accruing interest. File now — the penalty doesn't stop growing while you wait.
Enter your miles and gallons by state. The calculator handles the tax math instantly — free, no account required.
Open IFTA Calculator →IFTA math looks intimidating until you understand what it's actually doing: it's calculating your fleet's average fuel economy across all miles, then figuring out what you should have paid in fuel tax per state — and comparing it to what you actually paid at the pump.
If this math sounds tedious, that's because it is when done manually across 10+ states per quarter. Our IFTA fuel tax calculator does all of this automatically — enter your miles and gallons by state, and it produces the full breakdown including which states you owe and which owe you.
IFTA audits happen. The most common trigger is a discrepancy between your filed return and your ELD records or fuel receipts. Here's what to watch for.
Fuel tax rates vary significantly by state — and that difference directly determines whether you owe or get credited in each jurisdiction. High-tax states create liability when you drive miles there without buying fuel locally. Low-tax states generate credits when you fuel up there but drive the miles elsewhere.
Here are the Q2 2026 diesel tax rates for the 10 states where OTR owner-operators most commonly accumulate miles:
| State | Diesel Tax Rate (¢/gal) | Notes |
|---|---|---|
| Pennsylvania | 74.1¢ | Highest diesel tax in the US; avoid fueling here |
| California | 68.0¢ | Rate adjusts quarterly; verify before filing |
| Washington | 49.4¢ | One of the highest rates in the West |
| Indiana | 54.0¢ | Midwest corridor; high volume of OTR miles |
| Illinois | 46.7¢ | Chicago hub; expect significant miles here |
| Ohio | 47.0¢ | Major east-west corridor state |
| Texas | 20.0¢ | Low rate; favorable to fuel here vs. drive-through states |
| Florida | 36.1¢ | Southeast corridor; moderate rate |
| Georgia | 29.1¢ | Below national average; decent fueling option |
| Tennessee | 27.4¢ | One of the lower rates in the Southeast |
Rate arbitrage matters. A Pennsylvania run where you fuel up in Ohio (47¢) instead of PA (74¢) saves you 27¢ per gallon at the pump — and IFTA credits you for the miles driven at Pennsylvania's higher rate. That's a double win on high-mileage PA runs.
The strategic implication for owner-operators: when planning a run through a high-tax corridor state like Pennsylvania or California, fuel up in the lower-tax neighboring state before entering. You'll pay less at the pump, and IFTA will credit you the difference between what you paid and what you owed in the high-tax state. It won't eliminate your IFTA liability for driving those miles — but it reduces your all-in fuel cost per mile on that run.
The NetMile IFTA calculator uses current Q2 2026 rates for all 48 IFTA states. Enter your state-by-state miles and gallons and it shows you exactly which states you owe and which ones owe you.
IFTA isn't complicated once you understand the logic. It's just fuel-tax accounting: the states want their share based on where you drove, you want credit for what you already paid at the pump. The quarterly return reconciles the two.
What trips up owner-operators isn't the math — it's recordkeeping. Missing a state, using the wrong rate, or losing a fuel receipt creates discrepancies that trigger audits or shortchange your refund. Keep clean Q2 records now, while the quarter is in progress, instead of trying to reconstruct them in late May.
May 31 is the hard deadline. Run your IFTA calculation now so you know whether you owe or are owed — and how much. No surprises at the end of the month.
The IFTA calculator on NetMile handles the full calculation in under two minutes. Enter your states, your miles, your gallons — and it produces a complete breakdown of your Q2 tax position before you file. Free, no account required.
Enter miles and gallons by state. Get a full IFTA summary: what you owe each state, what credits you're owed, and your net total. Takes 2 minutes.
Calculate My IFTA Tax →