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Marijuana Laws to Know

Massachusetts residents voted to legalize cannabis use for medical purposes in 2012 and retail sale of cannabis prodcuts in 2016. This page provides general information about the laws regarding cannabis. For more complete information about these laws, visit the Cannabis Control Commission website
Click here to download a Fact Sheet about Cannabis Law.


Cannabis bought from licensed dispensaries is inspected to ensure that it is free of additives, chemicals, molds, and mites. Inspections also confirm the amount of the active substances in the cannabis products such as THC and CBD. Purchasing cannabis products from anywhere other than a licensed dispensary is illegal and it is more likely to contain harmful chemicals, heavy metals, pesticides and other substances.


The law prohibits smoking or consuming cannabis of any kind in any public place, including public parks, sidewalks, bars or restaurants. Residents can carry up to one ounce of cannabis in public. Five grams of that ounce may in the form of cannabis concentrate (such as dabs or wax).


It is illegal to operate a vehicle under the influence of cannabis. It is also illegal to have open containers of cannabis in a vehicle. Cannabis must be kept in a locked glove compartment or trunk. 


Residents 21 years old or older can grow no more than 6 cannabis plants. There can be no more than 12 plants in a household. Plants must be grown in a locked or secured location.


Many apartment and condominium buildings have smoke-free / vape-free policies that cover cannabis. Some may also have rules prohibiting growing or consuming cannabison site. Using or growing cannabis in public housing could lead to the loss of housing.


The following resources were used in developing the material on this website and may provide additional helpful information about cannabis:

If you are looking for resources or support around cannabis or other substance use, please call 311. 

Boston Public Health Commission
1010 Massachusetts Ave, 6th Floor, Boston, MA 02118.
Phone:(617) 534-5395 Email: