Excises are prorated on a monthly basis. If a motor vehicle is registered after the beginning of any calendar year, no excise will be imposed for those months, if any, which have fully elapsed before the vehicle is registered. If a vehicle is registered for any part of a month, however, the excise will be due for all of that month. The annual excise due on a car registered after January 1 will be reduced, therefore , by one twelfth of the full year's excise for every month prior to the one in which the vehicle was registered.
Appears in: Motor Vehicle Excise Taxes FAQs