Connecticut Highway Use Tax: Rates, myconneCT Registration & Quarterly Filing

The Connecticut highway use tax is a quarterly per-mile charge on heavy commercial vehicles operating on any public road in the state. It applies to trucks with a gross weight of 26,000 pounds or more that fall within Federal Highway Administration Classes 8 through 13, took effect January 1, 2023, and is administered by the Department of Revenue Services under Connecticut General Statutes Chapter 222a, Section 12-493a.¹ DRS refers to it officially as the Highway Use Fee.²

Which Trucks Are Covered

Two conditions must both be met. The vehicle has to weigh at least 26,000 pounds gross, and it has to carry a Federal Highway Administration classification between Class 8 and Class 13.¹ That captures tractor-trailers, heavy dump trucks, concrete mixers, and similar large commercial vehicles. Lighter trucks, passenger vehicles, and most single-unit delivery vehicles fall below the threshold.

In-state and out-of-state carriers are treated the same. If your truck meets the weight and class criteria and touches a Connecticut public road, every mile driven in the state counts.²

The statute contains only two exemptions, both built into its definitions. Vehicles operated by the state of Connecticut, its political subdivisions, the United States government, and federal agencies are excluded because those entities are not “carriers” under the law. Vehicles transporting milk or dairy products to or from a licensed dairy farm are excluded from the definition of “eligible motor vehicle” even if they meet the weight and class thresholds.¹ There are no other carve-outs.

What You Owe Per Mile

The tax runs on a graduated schedule with 28 weight brackets. Multiply the per-mile rate for the vehicle’s gross weight by its total Connecticut miles for the quarter. The full schedule from Section 12-493a:¹

26,000–28,000 lbs: $0.0250 per mile
28,001–30,000 lbs: $0.0279 per mile
30,001–32,000 lbs: $0.0308 per mile
32,001–34,000 lbs: $0.0337 per mile
34,001–36,000 lbs: $0.0365 per mile
36,001–38,000 lbs: $0.0394 per mile
38,001–40,000 lbs: $0.0423 per mile
40,001–42,000 lbs: $0.0452 per mile
42,001–44,000 lbs: $0.0481 per mile
44,001–46,000 lbs: $0.0510 per mile
46,001–48,000 lbs: $0.0538 per mile
48,001–50,000 lbs: $0.0567 per mile
50,001–52,000 lbs: $0.0596 per mile
52,001–54,000 lbs: $0.0625 per mile
54,001–56,000 lbs: $0.0654 per mile
56,001–58,000 lbs: $0.0683 per mile
58,001–60,000 lbs: $0.0712 per mile
60,001–62,000 lbs: $0.0740 per mile
62,001–64,000 lbs: $0.0769 per mile
64,001–66,000 lbs: $0.0798 per mile
66,001–68,000 lbs: $0.0827 per mile
68,001–70,000 lbs: $0.0856 per mile
70,001–72,000 lbs: $0.0885 per mile
72,001–74,000 lbs: $0.0913 per mile
74,001–76,000 lbs: $0.0942 per mile
76,001–78,000 lbs: $0.0971 per mile
78,001–80,000 lbs: $0.1000 per mile
80,001 lbs and over: $0.1750 per mile

Watch the top of the table. A truck at exactly 80,000 pounds pays 10 cents per mile. One pound heavier and the rate jumps to 17.5 cents. On 1,000 Connecticut miles in a quarter, that single pound costs an extra $75.

Registering Through myconneCT

Before you can file, you have to register for a Highway Use Fee permit. Registration happens only through myconneCT, the DRS online portal. There is no paper option.²

Have the following ready before you start:

Legal business name and FEIN, or your Social Security Number if you are a sole proprietor.
USDOT number for your operation.
Vehicle Identification Number and gross weight for each truck in the fleet that meets the 26,000-pound, Class 8–13 threshold.

The portal walks you through each vehicle one at a time. A wrong VIN or weight here will cause mismatches later when your return calculations have to line up with your registered fleet.

Filing Quarterly Returns

Returns are quarterly, not monthly, and each one is due by the last day of the month following the end of the quarter.² The quarters track the calendar year, so the January–March return is due April 30, April–June is due July 31, July–September is due October 31, and October–December is due January 31.

Filing and payment both run through myconneCT. You enter each eligible vehicle’s Connecticut mileage for the quarter, and the system calculates the tax from the weight brackets. ACH debit and credit card are accepted. Save the confirmation number as proof of filing.²

Zero-mileage quarters still require a return. If your fleet drove no Connecticut miles, file showing zero. Skipping the filing is a common mistake that can trigger penalties.

Records You Have to Keep

Carriers must retain mileage logs, receipts, invoices, and supporting documents for at least four years after each return’s filing date.² DRS can request them any time inside that window.

At a minimum, your records should document each trip’s date, origin and destination, Connecticut miles, and the vehicle’s gross weight. Odometer or hubometer readings, fuel logs, bills of lading, and dispatch sheets all back up what you report. Electronic records are fine if they carry the same detail. Large fleets commonly pull mileage from GPS or Electronic Logging Device data, though the state does not require any particular tracking method.

Penalties for Late or Wrong Filings

A late or incomplete filing draws a penalty of 10% of the unpaid tax or $50, whichever is greater. Unpaid tax also accrues interest at 1% per month, or any fraction of a month, until paid.²

Serious violations carry heavier consequences under Connecticut’s motor carrier tax enforcement provisions. A deficiency found to result from fraud or intentional evasion is penalized at 25% of the deficiency. Willful failure to pay, file, or keep required records can bring a criminal fine of up to $1,000, up to one year of imprisonment, or both. Submitting a fraudulent document to DRS is a Class D felony.³

The per-mile rates are small. The enforcement framework around them is not. A bookkeeping lapse that leads to underreported mileage can snowball into a deficiency assessment with penalties and interest well above the original tax.

1
Connecticut General Assembly. Connecticut General Statutes Chapter 222a – Highway Use Tax
2
Connecticut State Department of Revenue Services. Highway Use Fee Information
3
Connecticut General Assembly. Connecticut General Statutes Chapter 222 – Motor Carrier Road Tax