Chapter 135 of the Acts of 2024[1], titled "An Act Modernizing Firearms Laws," was signed by Governor Maura Healey on July 25, 2024, and took effect on October 2, 2024. It is the most comprehensive overhaul of Massachusetts firearms law since Chapter 180 of the Acts of 1998.
What Changed
Chapter 135 touches nearly every section of the firearms code. The major changes include:
- Assault weapons ban restructure: Chapter 135 restructured the former assault weapons ban. Section 131M(a) now contains the primary prohibition on assault-style firearms, untraceable firearms (ghost guns), covert firearms, and post-cutoff large capacity feeding devices. Section 131M(b) and (c) provide the grandfathering framework. Section 128 was restructured to address dealer licensing violations and related offenses.
- LTC class elimination: Chapter 284 of 2014 eliminated the Class B LTC. Chapter 135 removed remaining class designation references, formalizing the single-class License to Carry.
- Untraceable firearm prohibitions: New Sections 121C and 121D created comprehensive requirements for firearm serialization and regulated the use of 3D printers and CNC machines to manufacture firearm components. The statute uses “untraceable firearm” and “privately made firearm” as the defined terms; “ghost gun” is the commonly used name.
- Extreme Risk Protection Orders: Sections 131R through 131Y, originally created by Chapter 123 of 2018, were expanded to remove the requirement that the respondent hold an active firearms license and to broaden who may petition for an order.
- Firearms dashboards: New public data reporting requirements for the state.
- Prohibited areas: Created a new list of locations where firearms may not be carried under Section 10(k): government administrative, judicial, and correctional buildings and grounds, and ballot-storage, tabulation, polling, and early voting locations. Hospitals and places of worship are not included.
- Tiered storage requirements: Updated safe storage standards in Section 131L based on household composition, including enhanced requirements for households with minors or prohibited persons.
Effective Dates
The law took effect on October 2, 2024, following the addition of an emergency preamble by Governor Healey. Certain provisions have phased implementation dates. The serialization requirements under Section 121C include compliance deadlines for owners of existing unserialized firearms. The Firearm Licensing Review Board under Section 130B, originally created by Chapter 284 of 2014, requires ongoing regulatory implementation.
Referendum Timeline
A petition to repeal Chapter 135 gathered sufficient signatures to place a referendum question on the November 3, 2026 ballot[2]. If a majority of voters approve the repeal, all provisions of Chapter 135 would be repealed retroactively. Until then, the law remains in full effect. The referendum creates legal uncertainty for individuals and businesses making long-term compliance investments.
Cross-References
Chapter 135 amendments are integrated throughout the statutory entries on this site. Individual section entries cover the specific changes in detail:
- Section 131 (LTC): Single-class license, suitability standard, Licensing Review Board
- Section 131M: Assault-style firearm prohibition (subsection a) and grandfathering (subsections b and c)
- Section 128: Restructured dealer licensing violations
- Sections 121C and 121D: Untraceable firearms and serialization
- Sections 131R through 131Y: Extreme Risk Protection Orders
- Section 131L: Updated storage requirements
Registration and Serialization Timeline
EOPSS announced in September 2025 that the online gun registration and serialization systems would launch in October 2025. Guidance Letter #4, issued November 13, 2025, provided updated implementation details. The statutory effective date for the live-fire training requirement is April 2, 2026, but final regulations have not been formally adopted as of March 2026.