Mass. Gen. Laws ch. 43 § 16A
The city primary and election under Plan F shall, except as otherwise provided in this chapter, be conducted under the provisions of the statutes of the commonwealth relating to party primaries and elections. The city primary shall be held on the sixth Tuesday preceding the regular city election. At said primary each political party shall place in nomination a candidate for mayor, six candidates for school committeeman, as many candidates for councillor-at-large as there are councillors-at-large to be elected, and a candidate for councillor from each ward of the city. There shall not be printed on the ballot at such city primary the name of any person as a candidate for nomination for the office of mayor, school committee, or city councillor, unless a certificate from the registrars of voters of the city wherein such person is a registered voter that he is enrolled as a member of the political party whose nomination he seeks is filed with the city clerk on or before the last day for filing nomination papers.
Nominations of candidates, other than party nominations for any offices to be filled at a city election may be made by nomination papers containing the name of the candidate, his residence with street and number, if any, the office for which he is nominated and the principle, if any, which he represents in not more than three words. If a candidate is nominated otherwise than by a political party, the name of a political party shall not be used in his political designation, nor shall the name of any organization which has been adjudicated subversive under section 18 of chapter 264, be used in his political designation.
Such nomination papers shall be signed in the aggregate by not less than such number of voters as will equal three per cent of the entire vote cast for governor at the preceding biennial state election in the electoral district or division for which the officers are to be elected, but in no event by less than fifty voters.
A nomination paper for city office shall be filed with the city clerk by a responsible person who shall sign his name and address. The written acceptance of the candidate shall be filed therewith.
Such independent nomination papers for city offices shall be filed not later than the last day fixed for the filing of party nomination papers for the city primaries.
Mass. Gen. Laws ch. 43, § 16A