How Much Is Annual Car Tax in CT: Calculation, Billing, and Reductions

For a typical three-year-old car with a $35,000 original sticker price, the annual car tax in CT comes to about $600. Connecticut treats every registered vehicle as taxable personal property, so instead of a flat registration fee you pay a yearly property tax to the town where the car is garaged. The bill depends on three things: your vehicle’s original manufacturer’s suggested retail price (MSRP), its age, and your town’s motor vehicle mill rate.

The Three Numbers That Set Your Bill

Starting with the October 1, 2024 grand list, Connecticut assessors no longer look up your car’s used-market value in a pricing guide. They start from the original MSRP and reduce it by a fixed percentage based on the vehicle’s age.¹ Two identical model-year cars pay the same tax regardless of mileage or condition.

The state-mandated depreciation schedule works like this:¹

Year 1 (up to one year old): 85% of MSRP
Year 2: 80%
Year 3: 75%
Year 4: 70%
Year 5: 65%
Year 6: 60%
Year 7: 55%
Year 8: 50%
Year 9: 45%
Year 10: 40%
Years 11 through 14: drops from 35% down to 20%
Years 15 through 19: 15%
20 years and older: assessed at no less than $500

A 2025 law lets towns adopt a schedule that is five percentage points higher across the board — 90% in year one instead of 85%, for example.² Ask your local assessor which version applies.

Once the depreciation percentage is applied, every Connecticut assessor multiplies the result by 70% to arrive at the assessed value. That ratio is statewide and applies to all property types, so your town cannot change it.³

The final piece is the mill rate. A mill is one dollar of tax per $1,000 of assessed value. Each town sets its own rate during its annual budget, but state law caps the motor vehicle rate at 32.46 mills.⁴ The cap took effect for the assessment year beginning October 1, 2021. Most Connecticut towns have overall mill rates above 32.46, which means most drivers are paying the capped rate.

Calculating Your Own Bill

Four steps will get you a close estimate:

Find your vehicle’s MSRP. The original window sticker works, or you can look up the base MSRP for your year, make, and model.
Multiply the MSRP by the depreciation percentage for your car’s age.
Multiply that result by 70% to get the assessed value.
Divide the assessed value by 1,000 and multiply by your town’s motor vehicle mill rate.

Worked example. A three-year-old car with an MSRP of $35,000 in a town using the 32.46 cap and the default depreciation schedule:

Depreciated value: $35,000 × 75% = $26,250
Assessed value: $26,250 × 70% = $18,375
Annual tax: ($18,375 ÷ 1,000) × 32.46 = $596.46

If the town adopted the optional higher schedule (80% in year three), the assessed value climbs to $19,600 and the tax to about $636. The gap widens for more expensive vehicles.

Which Town Bills You, and When

Your car is taxed by the town where it is registered as of October 1, which is the date Connecticut uses to compile the annual grand list.³ Move to a different Connecticut town during the year and the tax still goes to whichever town was on your registration on that date. There is no proration between municipalities, so update your registration promptly after a move.

Regular bills go out around the end of June with a July 1 due date. You have until August 1 to pay without penalty. Miss that grace period and interest accrues at 1.5% per month (18% annually) back to the original July 1 due date, with a $2 minimum charge.⁵ Any partial month counts as a full month, so paying even one day into August costs you two months of interest.

Supplemental Bills If You Registered Mid-Year

Buy or register a car after October 1 and before the following August and it won’t be on the regular grand list. You get a supplemental motor vehicle tax bill instead, due January 1 with a grace period through February 1. The tax is prorated by the number of months left in the assessment year from the month you registered. Vehicles first registered in August or September are skipped entirely because so little of the tax year remains.

Interest on supplemental bills works the same way: 1.5% per month from January 1 if payment doesn’t arrive by February 1.⁵

What Happens If You Don’t Pay

Unpaid motor vehicle taxes go beyond interest charges. Connecticut law requires the DMV to deny registration renewals and block new registrations for anyone a town has reported as delinquent.⁶ The DMV cannot clear the hold for you. The tax collector in the town you owe has to release the delinquency electronically.

Towns can also issue an alias tax warrant after a demand notice. When a marshal delivers it, the marshal collects 15% of the amount recovered (minimum $30) plus expenses. Accounts still unpaid after the demand notice may be sent to a collection agency, adding another 15% surcharge. These charges stack on top of monthly interest.

Ways Your Bill Might Be Lower

A few situations reduce or eliminate the tax. To claim any exemption you generally need to file paperwork with your local assessor before the grand list is finalized.

Older Vehicles

Any vehicle 20 years old or older is assessed at no less than $500.³ At the 32.46 cap, that produces an annual bill of $16.23. Antique, rare, and special interest vehicles as defined under Connecticut’s registration statutes are also capped at a $500 assessment regardless of actual market value.

Veterans

The state mandates exemptions for qualifying veterans in several categories: wartime service, retirement after 30 years of service, and a VA disability rating of 10% or higher. The base exemption for wartime veterans is $1,000 in assessed value. For veterans with disabilities the exemption ranges from $2,000 (10 to 25% rating) up to $3,500 (76 to 100% rating). Veterans who lost a limb or suffered other severe service-related disabilities receive additional exemptions of $5,000 to $10,000 in assessed value.⁷ These exemptions apply against your total property tax assessment, not the car alone, and many towns add local exemptions on top.

Leased Vehicles

If you lease, the leasing company is technically the owner liable for the tax. In practice most lessors pass it through, either baked into your monthly payment or billed separately after they pay the town.⁸ Check your lease to see which method applies.

Adjustments If You Sold, Totaled, or Moved

Sell your car, total it, donate it, or move out of state and you can request a prorated adjustment from the town assessor. You have 27 months from the assessment date to provide proof, or you lose the right to the adjustment. Two documents are required: your Connecticut DMV plate cancellation receipt, plus one additional form of proof.

Sold: bill of sale signed by the buyer, a copy of the new owner’s registration or title, or a copy of your title showing the transfer.
Totaled: a letter from your insurer confirming the total loss, or a dated receipt from the salvage buyer.
Moved out of state: a copy of the vehicle’s registration or title in your new state.
Stolen and not recovered: a letter from your insurer or a police report confirming the theft and non-recovery.
Donated: a letter from the charity confirming the donation date and vehicle details.

The DMV does not tell your town when you cancel plates, so the paperwork is on you. Contact the assessor as soon as the car is gone.

Appealing an Assessment That Looks Wrong

If the assessed value looks too high — say the MSRP on file is wrong, or the model year is off — start with a call to the assessor’s office. Simple errors in MSRP, model year, or vehicle identification can often be corrected without a formal appeal.

If you need to appeal formally, written applications for the regular grand list are due to the assessor by February 20, and the Board of Assessment Appeals hears the case. Most towns also run a separate September session specifically for motor vehicle appeals, which does not require a pre-filed application. Bring documentation supporting the value you believe is correct, such as a purchase agreement or evidence of damage.

1
Connecticut General Assembly. An Act Concerning Motor Vehicle Assessments
2
Town of Wethersfield. Motor Vehicle Assessment Changes
3
Justia Law. Connecticut Code 12-71 – Personal Property Subject to Tax
4
Justia Law. Connecticut General Statutes 12-71e – Motor Vehicle Mill Rate
5
Justia Law. Connecticut General Statutes 12-146 – Delinquent Tax or Installment, Interest, Waiver of Interest
6
Department of Motor Vehicles. Compliance Issues
7
Connecticut General Assembly. Veterans Property Tax Exemptions by Town – State-Mandated Exemptions
8
Connecticut General Assembly. Local Taxes on Leased Cars