How is IFTA quarterly fuel tax calculated?

IFTA calculates your fleet's average MPG (total miles divided by total gallons purchased across all states). Then for each state, it computes fuel used (miles in that state divided by avg MPG) and compares to fuel purchased there. If fuel used exceeds fuel purchased, you owe that state's tax rate times the difference. If fuel purchased exceeds fuel used, that state refunds the difference.

Which state has the highest diesel fuel tax rate for IFTA?

Pennsylvania has the highest diesel fuel tax rate in the US for IFTA purposes at approximately 74.1 cents per gallon in 2025. Indiana is second at 53.0 cents per gallon, followed by New Jersey and Washington at 49.4 cents each. The lowest rates are in Missouri (17.0c), Mississippi (18.0c), and Oklahoma (19.0c).

When are IFTA quarterly returns due?

Q1 (Jan-Mar) due April 30. Q2 (Apr-Jun) due July 31. Q3 (Jul-Sep) due October 31. Q4 (Oct-Dec) due January 31. Late filing penalty is 10% of net tax due or $50, whichever is greater, plus interest.

⛽ IFTA Quarterly Return | 48 US States | 2025 Diesel Rates

IFTA Fuel Mileage Calculator: Quarterly Fuel Tax Return for All 48 States

Calculate your quarterly IFTA fuel tax return for every jurisdiction you operated in. Add states, enter miles driven and gallons purchased per state, and the calculator shows exactly what you owe or what refund you are owed from each jurisdiction. Built-in 2025 diesel tax rates for all 48 IFTA member states.

✓ All 48 IFTA Member States ✓ 2025 Diesel Fuel Tax Rates ✓ Owe vs Refund Per State ✓ Average Fleet MPG Auto-Calculated ✓ PDF Quarterly Return Prep Sheet ✓ Dynamic Jurisdiction Table

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IFTA Quarterly Fuel Tax Calculator

Enter miles and gallons purchased per state. Defaults pre-loaded with a Chicago-Nashville Q3 example. Click Calculate to see results.

Jurisdiction Table: Miles Traveled and Fuel Purchased by State (This Quarter)

Add one row per IFTA jurisdiction you operated in this quarter. Enter total quarterly miles for each state and total gallons purchased (at the pump) in that state. Gallons purchased can be zero if you drove through without fueling. The calculator determines average fleet MPG from totals and computes each state’s tax position automatically.

Jurisdiction	Miles Traveled This Quarter	Gallons Purchased This State

What IFTA Is and Which Carriers Must File a Quarterly Return in the United States

IFTA stands for International Fuel Tax Agreement, a cooperative compact among the 48 contiguous US states and 10 Canadian provinces that simplifies how commercial carriers report and pay fuel taxes when they operate across multiple jurisdictions. Before IFTA took effect in 1996, a carrier operating in 15 states needed to obtain a separate fuel tax license in each state, track fuel purchases per state with separate accounting, and file 15 separate quarterly returns. IFTA replaced that system with a single license from the carrier’s base jurisdiction, one quarterly return, and one payment or refund to the base state, which then handles the distribution of funds to every other jurisdiction the carrier operated in.

The core concept is straightforward: every qualified motor vehicle burns fuel at a consistent average rate across all miles driven, regardless of where those miles occur. IFTA calculates the fuel that should have been used in each jurisdiction based on miles driven there and the fleet’s overall average MPG. It then compares that calculated fuel consumption against the actual fuel purchased in each jurisdiction. If you burned more fuel in a state than you purchased there, you owe that state fuel tax on the difference. If you purchased more fuel in a state than you burned there, that state owes you a refund. All these net positions are summed across every jurisdiction you operated in, and the total is either your quarterly tax payment to your base state or your quarterly refund from it.

IFTA Quarterly Deadlines: Q1 (January-March) due April 30. Q2 (April-June) due July 31. Q3 (July-September) due October 31. Q4 (October-December) due January 31. Late returns are subject to a penalty of 10 percent of the net tax due or $50, whichever is greater, plus interest on unpaid taxes. Source: IFTA.org

Which Vehicles Must Have an IFTA License

IFTA applies to any qualified motor vehicle that is used in two or more IFTA member jurisdictions. A qualified motor vehicle meets any of the following criteria: it has two axles and a gross vehicle weight or registered gross vehicle weight exceeding 26,000 pounds; it has three or more axles regardless of weight; or it is used in combination with other vehicles where the combination exceeds 26,000 pounds. Most commercial 18-wheelers, flatbeds, tankers, and refrigerated trailers fall under the first or second criteria. Pickup trucks and passenger vehicles do not qualify. Recreational vehicles used strictly for personal purposes are also exempt. If your vehicle crosses state lines and meets the weight criteria, you need an IFTA license, even if you only operate in two states.

Alaska and Hawaii are not IFTA members. If your operations are confined to Alaska or Hawaii, or you only cross into non-IFTA jurisdictions, different rules apply. The District of Columbia is also not an IFTA member, though DC has separate fuel tax agreements with surrounding states. For carriers whose entire operation is within a single state, no IFTA license is required, though they must still comply with that state’s intrastate fuel tax requirements.

Your Base Jurisdiction and What It Means for IFTA Filing

Your base jurisdiction is the IFTA member state where your qualified motor vehicles are registered, where your operational records are maintained, and from which your fleet operates. This is typically the state where you are domiciled as a carrier. The base jurisdiction issues your IFTA license and decals, processes your quarterly returns, and handles all collections and distributions to other member states on your behalf. If you are based in Illinois, you file a single IFTA return with the Illinois Department of Revenue every quarter, regardless of how many states you operated in that quarter.

Choosing the correct base jurisdiction matters for more than just convenience. The base state has the authority to audit your IFTA records, and its audit standards and procedures apply to your filings. Some states are known for more aggressive IFTA audit programs than others. Your base jurisdiction must be the state where you actually operate from, not a state you choose for tax strategy purposes. Registering in a state where you have no actual presence to gain a tax advantage is specifically prohibited under IFTA rules.

How the IFTA Fuel Mileage Calculator Works: The Math Behind Every Line of Your Quarterly Return

The IFTA calculation follows a specific sequence that the calculator replicates exactly. Step one is computing your fleet’s average MPG for the quarter. This is not an estimate or a specification figure from the manufacturer. It is your actual average, calculated by dividing total miles driven across all IFTA jurisdictions by total gallons of fuel purchased across all IFTA jurisdictions. Every quarter, this number changes based on your actual driving conditions, load weights, weather, and routes.

Step two applies that average MPG to each individual state. The fuel you were required to use in, say, Indiana this quarter equals the miles you drove in Indiana divided by your fleet average MPG. This is what IFTA considers the correct amount of fuel tax you should pay to Indiana, based on the fuel you actually burned on Indiana’s roads. If your average MPG was 6.67 and you drove 1,300 miles in Indiana, IFTA calculates that you burned 195 gallons on Indiana highways.

Step three determines what you actually paid Indiana in fuel taxes. If you purchased 0 gallons in Indiana, you paid Indiana zero in embedded fuel taxes at the pump. Indiana’s fuel tax is 53.0 cents per gallon in 2025. You owed Indiana 195 gallons times 53.0 cents, which is $103.35, and you paid $0 at the pump there. So your net position in Indiana is $103.35 owed. In contrast, if you purchased 650 gallons in Illinois at 46.7 cents per gallon but only burned 390 gallons there based on your average MPG, you overpaid Illinois by 260 gallons. Illinois owes you a refund of 260 times 46.7 cents, which is $121.42.

The IFTA calculator on this page automates all of these steps simultaneously for every state in your quarterly return. Add each state where you operated, enter quarterly miles and gallons purchased, and it computes the fleet average MPG, applies it to every state, and shows the net tax position for each jurisdiction. The bar chart visualizes which states you owe and which owe you, making route optimization decisions visually obvious.

Three Real US Carrier Scenarios: IFTA Returns Calculated for Q3 2025

Chicago, IL

IL-based carrier, Nashville corridor: buying smart in Illinois

IL: 2,600 mi, 650 galREFUND $121.42

IN: 1,300 mi, 0 galOWE $103.35

KY: 780 mi, 0 galOWE $32.76

TN: 1,820 mi, 325 galREFUND $14.04

Total: 6,500 mi, 975 gal6.67 MPG

NET: $0.65 owed (nearly balanced). Buying in IL and TN offset IN and KY obligations precisely.

Dallas, TX

TX-based carrier, TX-CA quarterly run: California rate impact

TX: 4,800 mi, 900 galREFUND $51.25

NM: 1,600 mi, 240 galREFUND $5.81

AZ: 1,200 mi, 0 galOWE $41.84

CA: 900 mi, 0 galOWE $54.32

Total: 8,500 mi, 1,140 gal7.46 MPG

NET: $39.10 owed. California at 45.0c/gal is the single largest liability even for just 900 miles driven.

Pittsburgh, PA

PA-based carrier, Northeast corridor: PA rate works in your favor

PA: 3,200 mi, 750 galREFUND $267.82

NY: 2,100 mi, 0 galOWE $122.15

NJ: 820 mi, 100 galREFUND $0.21

CT: 480 mi, 0 galOWE $25.94

MA: 400 mi, 0 galOWE $11.66

Total: 7,000 mi, 850 gal8.24 MPG

NET: $108.29 REFUND. PA’s 74.1c/gal rate is the highest in the US. Fueling heavily in PA creates a large refund buffer.

Chicago: Why a Nearly Balanced IFTA Return Is the Goal of Smart Fuel Buying

The Chicago-based carrier running a Nashville corridor quarterly illustrates the ideal outcome of strategic IFTA fuel buying. Illinois has one of the highest diesel fuel tax rates among Midwest states at 46.7 cents per gallon. That rate works against you at the pump, but it works for you on your IFTA return. By purchasing 650 gallons in Illinois and 325 gallons in Tennessee, this carrier pre-paid fuel taxes in the highest-rate states on the route. Indiana, with the second-highest rate in the country at 53.0 cents per gallon, was driven through without any fuel purchases, creating a $103.35 obligation to Indiana. But that obligation was almost perfectly offset by the $121.42 Illinois refund, leaving a quarterly net of just $0.65 owed.

This result does not mean the carrier made money on IFTA. It means they paid the correct amount of fuel tax to the correct states, with the IFTA system redistributing what they overpaid in Illinois and Tennessee to Indiana and Kentucky. The lesson is that the states with the highest fuel tax rates represent the biggest swings on an IFTA return: buying in a high-rate state creates large refunds, while driving through high-rate states without buying creates large obligations. The most sophisticated carriers map their refueling stops to high-tax states on outbound legs and buy minimally in low-tax states, reducing their net quarterly payment while keeping their IFTA return clean.

California: Why 900 Miles in a 45-Cent State Costs More Than 1,200 in Arizona

The Texas carrier’s quarterly return shows a pattern common to any carrier doing southwestern US runs: California creates a disproportionate IFTA obligation relative to the miles driven there. At 45.0 cents per gallon, California’s diesel fuel tax rate is more than twice Texas’s 20.0 cents. The Texas carrier drove 900 miles in California and purchased no fuel there. At 7.46 MPG average, that is 120.7 gallons consumed in California. At 45.0 cents per gallon, the IFTA obligation to California is $54.32. Arizona, where 1,200 miles were driven at 26.0 cents per gallon, created a $41.84 obligation. California generated more tax liability from 300 fewer miles purely because of its significantly higher fuel tax rate.

The takeaway for fleet managers optimizing CA-corridor routes: buying fuel in California is expensive at the pump, but it reduces IFTA obligations. If this carrier had purchased 120 gallons in California (roughly filling up once), the California IFTA obligation would drop from $54.32 to zero. The net-of-pump-price impact depends on whether California’s pump price premium over Texas exceeds the IFTA savings, but for carriers making frequent California runs, the IFTA math is part of the fueling decision every time they cross the state line.

Pennsylvania: The Highest Diesel Tax Rate in the US Creates a Large IFTA Refund Buffer

Pennsylvania’s diesel fuel tax rate of 74.1 cents per gallon is the highest of any US state. For a Pennsylvania-based carrier running Northeast corridors, this creates an unusual IFTA dynamic: every gallon purchased in Pennsylvania pays 74.1 cents in state fuel taxes, but the obligations in neighboring states like New York (47.9 cents), New Jersey (49.4 cents), and Connecticut (44.5 cents) are all lower. When a Pennsylvania carrier buys 750 gallons in the home state and burns only 388.6 gallons there (the rest going to drive to NY, NJ, CT, and MA), Pennsylvania owes that carrier a refund on the 361.4 gallons that were purchased but used outside Pennsylvania. At 74.1 cents per gallon, that refund is $267.82, which more than offsets the combined obligations to New York ($122.15), Connecticut ($25.94), and Massachusetts ($11.66). The net quarterly position is a $108.29 refund.

This result might look like Pennsylvania is subsidizing operations in neighboring states, but that is exactly how IFTA is designed to work. Pennsylvania collects the tax at the pump, and IFTA’s distribution mechanism returns the portion attributable to miles driven in other states to those states, while keeping what is owed for miles driven in Pennsylvania. The Pennsylvania carrier pre-paid taxes for NY, CT, and MA through the pump, and IFTA settles the accounts at quarter end. For carriers based in high-tax states, understanding this dynamic helps with cash flow planning: the large IFTA refund check arriving after quarterly filing is predictable and budgetable, not a surprise.

Six Expert Tips for IFTA Compliance and Reducing Your Quarterly Tax Bill

Tip 01

Buy Fuel in the Highest-Rate States on Your Route

Every gallon you purchase in a high-tax state (Pennsylvania at 74.1 cents, Indiana at 53.0 cents, New Jersey at 49.4 cents, Washington at 49.4 cents) is a gallon that reduces your IFTA obligation in that state. If you drive through Indiana without buying fuel, you owe Indiana 53.0 cents for every gallon you burned there. If you buy in Indiana before driving through, you pre-pay that obligation at the pump and reduce your quarterly IFTA payment. Strategic refueling at high-rate states is not tax avoidance; it is exactly how IFTA is intended to work, ensuring each state gets its tax revenue from the carrier regardless of where the fuel was purchased.

Tip 02

Track Miles by State Every Trip, Not Every Quarter

The single biggest source of IFTA audit findings is estimated or reconstructed mileage. Every trip your qualified motor vehicles make should produce a trip sheet or ELD record that shows miles driven in each state with a GPS or odometer basis. Reconstructing quarterly mileage from toll receipts, fuel receipts, or driver recollection is an audit risk because reconstruction errors are common and the burden of proof in an IFTA audit is on the carrier. Modern ELD systems automatically track jurisdiction crossings and miles per state. If your ELD does not have this feature, implement a manual trip sheet that drivers complete at every state line crossing, at every stop, and at the end of every shift.

Tip 03

Keep Fuel Receipts for Four Years, Not Three

IFTA requires member jurisdictions to retain records for a minimum of four years, but many states audit beyond that period for fraud cases. Keep original fuel receipts or credit card statements showing the date, seller, location, type of fuel, and number of gallons for every fuel purchase. Receipts must be readable: faded thermal paper receipts may not be acceptable during an audit. Many carriers scan receipts immediately and store them digitally. Bulk fuel purchases from your own depot or tank require internal documentation showing the same information as a pump receipt, including the vehicle that received the fuel, the quantity, the date, and the location. Missing receipts during an IFTA audit result in the auditor disallowing those gallons from your purchased column, which increases your calculated tax liability for every state you drove through.

Tip 04

Run a Pre-Quarter Calculation to Estimate Your Tax Position

Before each quarter ends, run a preliminary IFTA calculation using your miles-to-date and gallons-to-date. This gives you two or three weeks to adjust your refueling strategy for the remaining weeks of the quarter. If you see that you will owe a large amount to a specific high-rate state like Indiana or New York, plan to buy additional fuel in that state during your remaining runs. A proactive quarter-end fueling adjustment of 100 to 200 gallons in the right state can reduce a quarterly payment by $50 to $100. This calculator makes that kind of what-if analysis instant: change the gallons purchased in one state and recalculate to see the effect on your net quarterly position before you commit to a fueling stop.

Tip 05

Understand Why Your MPG Changes Your Tax Bill

Your average fleet MPG is the denominator in every IFTA calculation. A higher MPG means less calculated fuel consumption per state, which reduces your IFTA obligations in states where you drove without buying. A lower MPG means more calculated fuel consumption, potentially increasing your obligations. When your fleet gets new equipment with better fuel economy, your IFTA position in high-tax, no-purchase states improves because you calculate less fuel burned there. Conversely, a quarter with heavy loads, winter weather, or significant idle time will show lower MPG and higher calculated fuel consumption. Factor your typical seasonal MPG variation into your fueling strategy, buying more in high-rate states during low-MPG quarters and less during high-MPG quarters to maintain a balanced quarterly position.

Tip 06

File On Time Even If You Cannot Pay the Full Amount

The penalty for late IFTA filing is 10 percent of the net tax due or $50, whichever is greater, plus interest on unpaid balances at a rate set by each member jurisdiction. The penalty for filing on time but not paying in full is only the interest on the unpaid amount, which is substantially lower than the 10 percent late-filing penalty. If you have a large quarterly tax bill you cannot fully pay by the due date, file the return on time and pay what you can. Contact your base jurisdiction’s motor carrier or IFTA division to discuss a payment arrangement for the balance. Most base states have programs for carriers with temporary cash flow issues, and entering a payment agreement generally stops the accumulation of additional penalties while the agreement is in effect. Never skip filing because you cannot pay; the compounding penalties and potential license suspension for non-filing are far more costly than the interest on a late payment.

2025 Diesel Fuel Tax Rates by State: All 48 IFTA Member Jurisdictions

The rates below are approximate 2025 diesel fuel excise tax rates used by IFTA for quarterly calculations. Rates are expressed in cents per gallon. Rates change quarterly in some states and annually in others. Always verify current rates on your base state’s IFTA return or at IFTA.org before filing an official return. Pennsylvania consistently posts the highest rate and Missouri the lowest among the 48 states.

State	Rate (c/gal)	State	Rate (c/gal)	State	Rate (c/gal)
Pennsylvania	74.1c	New Jersey	49.4c	Oregon	38.0c
Indiana	53.0c	Washington	49.4c	Rhode Island	34.0c
Washington DC*	24.6c	New York	47.9c	Idaho	32.0c
California	45.0c	Ohio	47.0c	Vermont	32.0c
Connecticut	44.5c	Illinois	46.7c	Iowa	32.5c
North Carolina	40.6c	Maryland	36.9c	Wisconsin	32.9c
Florida	36.4c	West Virginia	35.7c	Nebraska	29.6c
Georgia	31.4c	Maine	31.2c	Alabama	29.0c
Utah	31.9c	Minnesota	28.5c	Nevada	29.1c
Arkansas	28.7c	South Dakota	28.0c	Kentucky	28.0c
Montana	27.8c	Tennessee	27.0c	Virginia	27.8c
Michigan	26.3c	Arizona	26.0c	Kansas	26.0c
Massachusetts	24.0c	Wyoming	24.0c	Colorado	22.0c
New Hampshire	22.2c	New Mexico	22.9c	Delaware	22.0c
North Dakota	23.0c	South Carolina	23.0c	Louisiana	20.0c
Texas	20.0c	Oklahoma	19.0c	Mississippi	18.0c
Missouri	17.0c

*DC not a full IFTA member; shown for reference. Rates approximate 2025 values. Pennsylvania is the highest at 74.1c/gal. Missouri is the lowest at 17.0c/gal. California at 45.0c/gal is the highest among the western states. Verify current quarterly rates at your base state’s IFTA division or IFTA.org before filing.

Frequently Asked Questions About IFTA Quarterly Returns and Fuel Tax Filing

IFTA (International Fuel Tax Agreement) is a cooperative compact among 48 contiguous US states and 10 Canadian provinces that simplifies fuel tax reporting for interstate commercial carriers. You are required to have an IFTA license if you operate a qualified motor vehicle in two or more IFTA member jurisdictions. A qualified motor vehicle is any commercial vehicle that has two axles and a gross vehicle weight exceeding 26,000 pounds, OR has three or more axles regardless of weight, OR is used in combination where the combination exceeds 26,000 pounds. If you operate only in one state, you need a state-only fuel tax permit, not an IFTA license. Alaska and Hawaii are not IFTA members, so operations confined to those states use different fuel tax systems. Contact your base state’s motor carrier division for the specific license application process.

IFTA quarterly returns are due on the last day of the month following the end of each quarter: Q1 (January through March) is due April 30; Q2 (April through June) is due July 31; Q3 (July through September) is due October 31; and Q4 (October through December) is due January 31. If the due date falls on a weekend or state holiday, most states extend the deadline to the next business day. Late filing penalties are generally 10 percent of the net tax due or $50, whichever is greater, plus interest on unpaid taxes at a rate that varies by jurisdiction but is typically in the range of 1 percent per month. Failure to file for multiple consecutive quarters can result in revocation of your IFTA license, which would prohibit you from legally operating your qualified motor vehicles across state lines until the license is reinstated. Always file on time even if you cannot pay the full amount; the late filing penalty is more expensive than the interest on a late payment.

Your fleet average MPG for IFTA is calculated by dividing total miles driven in all IFTA jurisdictions during the quarter by total gallons of fuel purchased in all IFTA jurisdictions during the quarter. This is a single average for all vehicles in your fleet if you file a combined return, or per-vehicle if you maintain separate vehicle records. It uses your actual miles and actual fuel purchases, not the vehicle manufacturer’s rated fuel economy. A fleet that drove 50,000 total miles and purchased 7,000 total gallons would have an average fleet MPG of 7.14 for that quarter. This average is then applied uniformly to calculate the fuel consumed in each individual state: a state where you drove 3,000 miles would be calculated as having consumed 3,000 divided by 7.14, which equals 420.2 gallons, regardless of what the trucks actually used on that particular road segment. The same average MPG is applied to every state, which is why your actual fueling choices affect the calculated obligations in states where you did not buy fuel.

If you purchased all your fuel in one state for the entire quarter, that state effectively pre-collected fuel taxes for every other state you drove through. Your IFTA return will show a large refund from your purchase state and owed amounts to every other state you operated in. The net of all these positions will generally be close to zero (the total tax collected at the pump across all your purchases equals approximately the total tax owed across all your miles, since the average MPG calculation normalizes it), but there will be individual state imbalances. For example, a carrier based in Missouri who buys all fuel in Missouri and drives through Indiana, Ohio, and Pennsylvania will get a refund from Missouri and owe significant amounts to the high-rate states. This is legal and acceptable under IFTA, but it does require making a quarterly payment to your base state that covers the net obligations, which can affect cash flow. Diversifying fuel purchases across high-rate states on your route reduces the size of individual state obligations and smooths out quarterly cash flows.

Pennsylvania has the highest diesel fuel tax rate in the US at approximately 74.1 cents per gallon in 2025, roughly twice the national average. Indiana is second at 53.0 cents, followed by New Jersey and Washington at 49.4 cents each, and New York at 47.9 cents. Ohio at 47.0 cents and Illinois at 46.7 cents round out the top tier of high-rate states, all of which are in the Midwest and Northeast industrial corridors. The lowest rates are concentrated in the South and lower Midwest: Missouri at 17.0 cents per gallon, Mississippi at 18.0 cents, Oklahoma at 19.0 cents, and Texas and Louisiana at 20.0 cents each. California at 45.0 cents is by far the highest rate in the West. The spread between the highest (Pennsylvania at 74.1 cents) and the lowest (Missouri at 17.0 cents) is 57.1 cents per gallon, which represents a significant IFTA calculation swing for carriers running routes between these states. Tax rates change periodically; always verify current rates with your base jurisdiction before filing an official return.

IFTA (International Fuel Tax Agreement) and IRP (International Registration Plan) are separate programs that are often administered together because they both apply to interstate commercial vehicles, but they serve completely different purposes. IFTA covers fuel taxes: it ensures each state receives the appropriate fuel tax revenue based on miles driven in that state, regardless of where the fuel was purchased. IRP covers registration fees and apportioned vehicle registration: it allows a carrier to register their vehicles in one base state and pay a single proportional registration fee that covers all the states where the vehicle operates, based on the percentage of total miles driven in each state. Without IRP, a carrier operating in 15 states would need 15 separate vehicle registrations. Both programs use your state-by-state mileage data, which is why many base states process IFTA and IRP together and why carriers who need one typically need both. The quarterly IFTA return uses total miles per state, while the annual IRP renewal uses total miles per state for the preceding year to calculate the next year’s apportioned registration fees.

Most base states now offer electronic IFTA filing through their motor carrier portals, and several states require electronic filing for carriers above certain size thresholds. Electronic filing is generally faster, reduces errors through built-in validation, and provides immediate confirmation of receipt. Most state IFTA portals allow you to enter mileage and fuel data directly or upload data from a spreadsheet in a specific format. Some states allow filing through third-party IFTA service providers who integrate with ELD systems to pull mileage data automatically and prepare the return on your behalf, which is common for larger fleets. Smaller carriers and owner-operators in states that still allow paper filing can use paper forms, but the trend across all 48 member jurisdictions is toward mandatory electronic filing. Check with your base state’s IFTA division for the current filing method requirements and any upcoming changes to mandatory electronic filing thresholds.

IFTA record retention requirements must be maintained for a minimum of four years from the filing date of the quarterly return, and in some jurisdictions for longer in cases of suspected fraud. The records you must keep include: individual vehicle mileage records showing the date of each trip, origin and destination, route, odometer or hubodometer readings at state line crossings, and miles per jurisdiction; fuel purchase receipts for every fuel purchase showing the date, seller name and address, type of fuel (diesel, gasoline, propane, etc.), number of gallons, and price; bulk fuel purchase records if you maintain your own fuel depot with the same information plus the vehicle receiving the fuel; and IFTA returns and any correspondence with your base jurisdiction regarding your account. Mileage records must establish a basis for the miles you report in each state. Acceptable basis includes GPS-supported trip records, ELD mileage reports, driver trip sheets with odometer readings, or a combination of these. Estimated or reconstructed mileage is an audit risk and may be challenged during an IFTA audit.

Yes, if your qualified motor vehicle crosses into any other IFTA member state at any point during the year, you are required to have an IFTA license and file quarterly returns, even if the crossing happens only once per quarter or once per year. There is no minimum mileage threshold in the other state. Even a single mile driven in a second state triggers the IFTA requirement for that vehicle during that quarter. Some carriers who make only occasional crossings into neighboring states find that the administrative burden of IFTA compliance outweighs the cost of simply purchasing trip permits for those individual crossings. Trip permits are single-use, state-issued documents that allow a non-licensed vehicle to make a specific trip into that state without an IFTA license. They are more expensive than IFTA per trip for frequent crossers but simpler for rare crossings. If your annual cross-state operations are fewer than about 10 trips per year, compare the cost of trip permits versus an IFTA license and the administrative overhead of quarterly returns to determine which is more economical for your operation.

IFTA audits are conducted by your base state’s IFTA audit team and may be triggered by several factors: random selection (all carriers have some audit probability regardless of compliance history), statistical anomalies in your returns (average MPG significantly above or below fleet norms for your vehicle type, mileage patterns that do not match known routes, fuel purchases that do not align geographically with mileage records), prior audit findings, tip-offs from weighmasters or other enforcement personnel, or failure to respond to notices from your base jurisdiction. During an audit, the auditor will request your original trip records, fuel receipts, ELD or GPS data, and may contact fuel vendors to verify purchase records. Audits typically cover four years of returns. If the audit finds underreported miles or over-claimed fuel purchases, you will owe additional tax plus interest and penalties. If the audit finds records fully support your returns or that you overpaid, you may receive a credit. Maintaining organized, complete records is the most effective audit defense. If you receive an audit notice, contacting your state’s IFTA division to understand the process before the audit date is advisable, and large carriers often engage a compliance consultant or tax attorney for significant audits.

IFTA requires separate tracking and reporting for each fuel type your fleet uses. Common fuel types that have separate IFTA reporting requirements include diesel, gasoline, propane, compressed natural gas (CNG), liquefied natural gas (LNG), ethanol, and hydrogen. Each fuel type has its own set of state tax rates, and the average MPG calculation is done separately for each fuel type. If your fleet includes both diesel trucks and CNG trucks, you maintain two separate fuel tracking records and report each fuel type on a separate section of your IFTA return. Mixed-fuel vehicles, such as vehicles that can run on both diesel and propane, require proportional accounting based on the fuel actually used. The tax rates for alternative fuels are typically lower than diesel rates in most states, reflecting the fuel’s energy content and various state policy decisions. This calculator handles diesel only; for CNG, LNG, or other alternative fuel fleets, contact your base jurisdiction’s IFTA division for fuel-type-specific rate sheets and return instructions.

Yes, quarterly IFTA refunds are common and represent the normal outcome when you purchase more fuel in a state than your calculated consumption there. As illustrated in the Pennsylvania example above, a carrier based in a high-tax state who buys heavily at home and drives significant miles in lower-tax neighboring states will typically receive a refund. Refunds are issued by your base jurisdiction, which collects the net payment from you when you owe, or pays the net refund when you are owed. Processing times vary by state but are typically 4 to 8 weeks after your return is filed and accepted. Some states issue paper checks; others can direct deposit if you set up electronic refund preferences on your account. If you expect a refund quarter, filing early (as soon as the quarter ends and your records are complete) will get the refund check to you faster. Do not delay filing to accumulate refunds, as this is not permitted; returns must be filed quarterly regardless of whether you owe or are owed.

Miles driven in non-IFTA jurisdictions (Alaska, Hawaii, the District of Columbia, the Yukon Territory before it joined IFTA in 2010, and US territories such as Puerto Rico and Guam) are tracked separately on IFTA returns under a category for unlicensed jurisdictions. Fuel purchased in non-IFTA jurisdictions is also tracked separately. These miles and gallons are included in your total fleet mileage and fuel calculations for MPG purposes, but they do not generate an IFTA tax position because there is no IFTA member jurisdiction to receive or refund tax. Alaska, for example, has its own intrastate fuel tax system. If you purchase fuel in Alaska, that fuel tax was paid directly to Alaska at the pump and does not appear in your IFTA return. If you drive in Alaska without buying fuel there, there is no IFTA mechanism to collect the difference; Alaska handles fuel tax collection for intrastate operations independently. Operations in Mexico are handled through separate international fuel tax agreements and are not part of the IFTA calculation.

Operating a qualified motor vehicle that requires an IFTA license without one, or without the required IFTA decals visible on the vehicle, is a serious violation that can result in significant fines, the vehicle being placed out of service, and in some states, criminal charges for the carrier. Fines for operating without an IFTA license vary by state but commonly range from $500 to $2,000 per incident. If the vehicle is stopped at a weigh station or a roadside inspection and found to lack valid IFTA credentials, the officer can order the vehicle held until a temporary permit or the IFTA license documentation is obtained. This can mean hours of delay and additional towing or administrative fees. The IFTA decals (which show the current year and your base jurisdiction) must be displayed on both sides of the cab, visible from outside the vehicle. IFTA licenses must be in the cab and available for inspection. Many states have moved to electronic verification systems, but the physical or electronic display requirement is still enforced. If you lose your decals or license, contact your base jurisdiction immediately for a replacement.

When an owner-operator leases their vehicle to a carrier under a lease agreement, the IFTA responsibility generally falls on the carrier whose authority the vehicle operates under, not the individual owner-operator. If an owner-operator’s truck runs under a carrier’s DOT number and operating authority, the carrier typically holds the IFTA license, and the owner-operator’s miles and fuel purchases are reported as part of the carrier’s combined IFTA return. The lease agreement should specify whether the owner-operator or the carrier is responsible for IFTA compliance, and the carrier should provide clear guidance on how to record and submit mileage and fuel data. If the owner-operator operates under their own authority (their own DOT number and MC number), they are the IFTA licensee and must file their own quarterly returns. Owner-operators who switch between leasing arrangements and operating under their own authority during the year may have IFTA obligations under both their individual license and the carrier’s license for different periods. Keep meticulous records of which authority the vehicle was operating under for each trip to ensure the correct IFTA account is credited with the miles and fuel for each operating period.

This calculator covers the 48 contiguous US states that are IFTA member jurisdictions for diesel fuel. Canadian provinces and territories that are IFTA members (Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, Quebec, and Saskatchewan, plus Yukon) are not included in this version. Canadian provinces have separate diesel fuel tax rates expressed in Canadian cents per liter, and the IFTA calculation requires currency conversion and unit conversion (miles to kilometers, gallons to liters) for cross-border operations. Carriers running US-Canada routes should use their base state’s IFTA return instructions for handling Canadian jurisdictions, as the method for reporting and converting Canadian figures varies slightly by base state. For US-only operations, this calculator covers all applicable jurisdictions. For Canadian province rates, refer to the most current IFTA rate bulletin published quarterly by your base state or available at IFTA.org.

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Legal Disclaimer and Editorial Transparency. The IFTA Fuel Mileage Calculator on this page is provided for planning and quarterly return preparation purposes only and does not constitute tax or legal advice. Diesel fuel tax rates shown are approximate 2025 values based on IFTA member state publications and may not reflect the current quarter’s rates. IFTA tax rates change quarterly in some jurisdictions. Always verify current rates with your base jurisdiction’s IFTA division or at IFTA.org before submitting an official quarterly return. This calculator covers the 48 contiguous US states that are IFTA members; Canadian provinces, Alaska, Hawaii, and US territories are not included. This calculator does not account for any fuel type other than diesel. Results should be verified against your base state’s official IFTA return form before filing. USCalculators.com is not affiliated with IFTA, Inc., any state DOT, or any government agency.