Massachusetts General Law Chapter 90, Section 2, is set up to allow a motor vehicle or trailer purchaser sufficient time to process the transfer of his/her current registration and to arrange for insurance coverage for a newly acquired vehicle.
The law allows a vehicle owner a period of seven (7) calendar days from the date he/she sold, traded, gifted, etc., or lost possession, of his/her currently registered motor vehicle or trailer to transfer the registration and registration plates to a newly acquired vehicle of the same type. During this seven-day period the owner may operate the newly acquired vehicle with the registration plates from the previously registered vehicle that he/she just lost possession of or sold, traded or gifted.
As an example of how the 7 days are calculated, if you sold or lost possession of the vehicle on June 17th, the 17th would be the first day and 5:00 pm of June 23rd would be the end of the seventh calendar day. Weekends and holidays are counted in the 7-day period. The transfer period begins as soon as you transfer ownership or lose possession of your currently registered vehicle.
If you do not have registration plates to transfer over you must follow the normal registration process and register your newly acquired vehicle (and attach the newly issued registration plates) before that vehicle may be operated on a public way. Any other operation is illegal.
Part of the normal registration process is to obtain insurance for the vehicle. Please note, there is no grace period if you do not currently have a registered vehicle or trailer. The RMV does not issue temporary registration plates. For more information on this process contact the MA Registry of Motor Vehicles.