Mass. Gen. Laws ch. 159 § 19A
The department may approve a rate, fare, toll or charge for directory assistance service pursuant to schedules filed with the department; provided, however, that for each business or residence line and for each private branch exchange trunk line to which a customer subscribes, said customer shall be entitled to receive an allowance of ten direct dialed directory assistance calls per month; provided, further, that as of January, nineteen hundred and ninety-three, directory assistance calls for telephone numbers which are non-listed, or non-listed and non-published shall not be included in the ten call allowance; and provided, further, there shall be no rate, fare, toll or charge for said calls. The department shall determine an appropriate reduced monthly direct dialed directory assistance call allowance applicable to each Centrex line to which a business customer subscribes to provide a monthly call allowance equivalent to the allowance provided to each private branch exchange trunk line. Customers who are certified handicapped or elderly pursuant to regulations promulgated by the department shall be allowed an unlimited number of directory assistance calls without charge, and subject to such other terms and conditions as the department finds reasonable; provided, however, that no rate, fare, toll or charge for directory assistance service may be charged to users of coin operated telephones. The department may approve a rate, fare, toll or charge for directory assistance service to other common carriers as defined in paragraph (d) of section twelve for such directory assistance service as provided for herein.
For the purpose of this section, "directory assistance service" or "directory assistance call" shall mean information given to a customer of a telecommunications company to provide such customer with a telephone number for another customer within the commonwealth. A telecommunications company that provides a service which gives customers information about telephone numbers in another state shall not be required to file a schedule with the department to offer such service and the department shall have no authority to review or approve the offering of such service. Each customer shall be entitled without charge to a directory for each area within the commonwealth.
Mass. Gen. Laws ch. 159, § 19A