IFTA & fuel tax — the quarterly you can't forget

What IFTA actually is

The International Fuel Tax Agreement (IFTA) is how the US and Canadian jurisdictions redistribute diesel fuel tax based on where you actually drive vs. where you buy fuel.

Example: you buy 100 gallons in Oklahoma (fuel tax: $0.20/gal) but drive most of your miles in Pennsylvania (fuel tax: $0.75/gal). At quarter-end, IFTA calculates you should have paid PA tax on the miles you drove there. IFTA sends the difference to Pennsylvania and bills you.

Meaning: buying "cheap fuel" in low-tax states doesn't actually save you money if you're driving in high-tax states. The tax settles up quarterly.

Who needs IFTA

You need an IFTA license if you operate a qualified motor vehicle in 2+ jurisdictions.

"Qualified motor vehicle":

• 2 axles AND GVWR > 26,000 lb, OR
• 3+ axles regardless of weight, OR
• Combination weight > 26,000 lb.

Your 26,000-lb GVWR box truck — technically borderline. Some states require IFTA, some don't at that exact weight. When in doubt, register. IFTA license is $10–$50 and the decals are $10/set. Missing IFTA when required = fine + back taxes.

The IFTA filing cycle

File a zero return in quarters you didn't operate — otherwise state pulls your license.

What you file

For each quarter, for each jurisdiction (state or Canadian province) you drove in:

• Total miles driven in that jurisdiction
• Total taxable miles
• Total gallons of fuel purchased in that jurisdiction
• Tax rate for that jurisdiction

The IFTA return calculates:

• Total fuel consumed (miles ÷ MPG)
• Tax owed per jurisdiction (fuel consumed × tax rate)
• Credit for fuel already purchased in each jurisdiction
• Net owed or refunded

The fuel receipts that matter

Every diesel purchase generates an IFTA-qualifying receipt if it includes:

• Date
• Vendor name
• Location (city, state)
• Fuel type
• Gallons purchased
• Price per gallon
• Total price
• Truck plate # or truck ID

Get a fuel card that captures this automatically:

• RTS Fuel Card — free with factoring, works at all major truck stops
• Comdata / EFS — industry standard
• Pilot Flying J Fuel Card — good discounts at Pilot/Flying J

Card statements auto-populate IFTA reporting. Cash purchases without receipts = zero credit on that gallon.

The MPG calculation

IFTA uses your actual MPG based on:

Total gallons purchased across ALL jurisdictions ÷ Total miles driven across ALL jurisdictions = Fleet-wide MPG

Then applies that MPG to each jurisdiction's miles to calculate fuel consumed there.

Example:

• 3,000 total miles for the quarter
• 350 total gallons purchased
• Fleet MPG: 3,000 ÷ 350 = 8.57 mpg
• 400 miles in Illinois → 400 ÷ 8.57 = 46.7 gallons consumed in IL
• Illinois fuel tax = $0.674/gal → tax owed = $31.48
• Fuel purchased in IL: 40 gallons × $0.674 = $26.96 credit
• Net owed to IL: $4.52

Do this for every state. Sum up. Pay quarterly.

The ELD-to-IFTA automation

Doing IFTA manually from receipts = a 4–6 hour nightmare each quarter.

Automated (via Motive, Samsara, KeepTruckin, or Trucker Path IFTA):

1. 1ELD tracks GPS mileage per state automatically.
2. 2Fuel card sync uploads receipts.
3. 3Software generates an IFTA-ready report.
4. 4You export, upload to your state's IFTA portal, pay.
5. 5Total time: 20 minutes.

This alone is worth the $25/mo ELD subscription.

Common IFTA mistakes

1. 1Not filing a zero return — costs you the license.
2. 2Estimating miles instead of using ELD — audit trigger.
3. 3Missing fuel receipts — you lose the credit.
4. 4Mixing personal miles into IFTA reporting — false report, penalty.
5. 5Not paying by due date — 10% penalty + interest.
6. 6Buying fuel out of state without recording — no credit.

The audit process

IFTA audits happen roughly every 3–5 years. Your base state auditor asks for:

• All fuel receipts for the audit period
• All ELD logs / mileage records
• Any drivers' logs on paper (if pre-ELD)
• IFTA returns filed

Keep receipts and reports for 4 years minimum. Cloud storage (Google Drive or Dropbox) with a folder per quarter is fine.

Rough IFTA reserve — the number to save

For most box truck operators running mostly Midwest/Southeast: budget $0.03–$0.05 per mile as IFTA reserve.

On 60,000 revenue miles/year, that's $1,800–$3,000/year. Set aside per week, pay quarterly.

If you run California / Northeast heavily, budget higher ($0.05–$0.07/mi) because tax rates are higher.

Action items

• Register for IFTA with your base state's DOT/DMV
• Buy IFTA decals for your truck (2 required — driver and passenger side)
• Set up ELD → IFTA automation in Motive/Samsara
• Set 4 recurring calendar reminders for quarterly due dates
• Open a separate savings sub-account labeled "IFTA reserve"
• Track weekly, reconcile monthly, file quarterly

Next: Factoring — how to get paid in 24 hours instead of 45 days.