Connecticut IFTA Fuel Tax Rate, 3rd Quarter 2025
Connecticut's IFTA diesel rate for the 3rd quarter of 2025 is $0.4890 per gallon, down $0.0350 from Q2 2025.
Connecticut rate for Q3 2025
Special diesel, Q3 2025
$0.4890
per US gallon, down $0.0350 from Q2 2025
- Diesel tax rate
- $0.4890/gal
- Surcharge
- None listed
- Quarter
- Q3 2025, from Jul 1, 2025
- Change vs last quarter
- down $0.0350
Notes from the source
Matrix footnote #15 (CONNECTICUT): See Announcement 2024(1) Conversion Factors on Motor Vehicle Fuels Occurring In Gaseous Form for information about conversion factors for compressed natural gas and propane. See Announcement 2025(2) Motor Vehicle Fuels Tax Rate on Diesel Fuel Effective July 1, 2025.
Worked example: the Connecticut line of your IFTA return
Change the numbers to match your quarter. Prefilled with 10,000 total miles on 1,550 gallons, 1,200 of those miles in Connecticut, and 100 gallons bought there.
Connecticut vs. its neighbors, Q3 2025
| Jurisdiction | Diesel + surcharge | vs. CT |
|---|---|---|
| Connecticut | $0.4890 | — |
| Rhode Island | $0.4000 | −$0.0890 |
| New York | $0.3875 | −$0.1015 |
| Massachusetts | $0.2400 | −$0.2490 |
On an IFTA return, a higher rate doesn't mean you pay more overall. Fuel you buy in a high-rate state earns a bigger credit. What matters is where you burn the fuel versus where you buy it.
Connecticut rate, last 4 quarters
Source: IFTA, Inc. Fuel Tax Rate Matrix, 3rd Quarter 2025 · Effective Jul 1, 2025 · Last verified Sep 28, 2026
IFTA, Inc. publishes the rates each member jurisdiction reports. Connecticut's tax agency is the final word on its rate.
Estimates for planning. Confirm with your tax pro or your base jurisdiction's IFTA office before filing.