The CT Mileage Tax: Who Is Required to Pay?

The term “CT mileage tax” can refer to two distinct programs. The first is the Highway Use Fee (HUF), a tax in effect for specific heavy-duty commercial trucks operating in Connecticut. This fee is calculated based on vehicle weight and miles driven within the state. It applies only to a select category of large vehicles and does not impact passenger cars or smaller trucks. The second program is a proposed, but not enacted, Vehicle Miles Traveled (VMT) tax, which involves taxing all drivers based on the number of miles they travel as a potential replacement for the gas tax.

The Enacted Highway Use Fee

Effective January 1, 2023, Connecticut implemented a Highway Use Fee that applies to certain heavy-duty motor vehicles. This fee is levied on any person or company that operates an eligible vehicle on any public road in the state. The law specifically targets multi-unit vehicles with a gross weight of 26,000 pounds or more, which fall within Class 8 to Class 13 of the Federal Highway Administration’s vehicle classification system.

Passenger cars, recreational vehicles (RVs), and smaller commercial vehicles that do not meet the 26,000-pound weight threshold are not subject to this tax. The fee is also specifically for multi-unit or combination vehicles, meaning straight trucks are not included.

The fee itself is calculated on a per-mile basis for all miles driven within Connecticut’s borders. The tax rate is tiered and increases with the vehicle’s gross weight, which includes the weight of its cargo. The rates begin at 2.5 cents per mile for vehicles in the 26,000 to 28,000-pound range. For vehicles weighing between 78,001 and 80,000 pounds, the rate is 10 cents per mile. The highest tier applies to vehicles weighing more than 80,000 pounds, which are taxed at a rate of 17.5 cents per mile.

Permit and Registration Requirements

Before a carrier can legally operate a qualifying heavy-duty vehicle in Connecticut, they must obtain a Highway Use Fee Permit. Obtaining this permit is mandatory for compliance, and there is no cost to register. The permit does not have an expiration date and does not require annual renewal. A single permit covers all eligible vehicles operating under a carrier’s authority.

The application process is handled entirely online through the Connecticut Department of Revenue Services (DRS) portal, myconneCT. This includes the legal name of the business, its address, and its U.S. Department of Transportation (USDOT) number. The application also requires a comprehensive list of all qualifying vehicles that will be operated in the state.

For each vehicle, the carrier must submit its Vehicle Identification Number (VIN) and its specific gross weight. Once the registration is processed, the permit becomes available electronically in the carrier’s myconneCT account. A copy of this permit must be kept inside every eligible vehicle operating in Connecticut.

Filing and Paying the Highway Use Fee

Carriers who have obtained a permit are obligated to file a Highway Use Fee Return quarterly. This requirement applies to all registered carriers, regardless of whether their vehicles traveled in Connecticut during a specific reporting period. The filing and payment process is managed through the myconneCT online portal.

To complete the quarterly return, carriers must have accurate mileage logs for each permitted vehicle. The filing requires the total number of miles driven in Connecticut by all eligible vehicles for the preceding calendar quarter. The deadline for filing the return and paying the fee is the last day of the month that follows the end of the calendar quarter.

Failure to file or pay on time results in penalties and interest. Interest accrues at a rate of 1% per month on the unpaid tax amount until it is paid in full. A penalty is assessed for late filing or incomplete returns, which is calculated at 10% of the tax due or $50, whichever is greater. Knowingly violating the statute can lead to a more significant penalty of $1,000.

Status of a Broader Vehicle Miles Traveled Tax

The discussion around a mileage tax for all vehicles in Connecticut stems from explorations into a Vehicle Miles Traveled (VMT) tax system. At present, no statewide VMT tax exists for passenger cars or other light-duty vehicles. A VMT tax is a user-fee system where drivers pay based on the number of miles they drive, rather than the amount of fuel they consume.

This model has been considered by various states as a potential long-term replacement for the gas tax, which is generating less revenue due to the increasing fuel efficiency of modern cars and the adoption of electric vehicles.

Connecticut has participated in pilot programs to study the feasibility and public acceptance of such a system. These pilot programs were for research purposes only and were designed to gather data on how a VMT system could be implemented. They explored different methods for tracking mileage and collecting payments.