Massachusetts Firearms Registration Deadline: October 28, 2026 — What Gun Owners Need to Know

By Attorney Joe Serpa | Georgetown University Law Center | 30 Years Massachusetts Criminal Defense

Massachusetts firearms owners face two separate compliance deadlines in October 2026, and much of the confusion in circulation comes from running them together. Under 501 CMR 20.00, implementing M.G.L. c. 140, § 121C, every firearm, frame, or receiver that lacks a serial number must be serialized by October 2, 2026. Under guidance issued by the Executive Office of Public Safety and Security, firearms already possessed before the state’s new registration portal came online must be registered through the portal by October 28, 2026. Missing either deadline converts a previously lawful owner into a criminal defendant in a state whose firearms statutes carry some of the harshest penalties in the country. This post explains where the deadlines come from, what each one requires, the penalty framework that applies when compliance fails, and why the clerk-magistrate hearing is the stage at which most compliance cases can still be contained.

How Massachusetts Got Here: Chapter 135 of the Acts of 2024

In July 2024, Governor Healey signed Chapter 135 of the Acts of 2024, An Act Modernizing Firearm Laws. It restructured the Commonwealth’s firearms code: it replaced the former assault weapon terminology with a broader assault-style firearm definition, expanded the definition of a firearm to include frames and receivers, finished or unfinished, created an electronic registration system codified at M.G.L. c. 140, § 121B, imposed the serialization requirement of § 121C, unified the license to carry by eliminating the old Class A and Class B distinction, broadened the extreme risk protection order framework of §§ 131R through 131Y, and expanded the list of prohibited areas where firearms may not be carried even with a valid license. For the underlying offense framework, see Massachusetts Firearms Defense.

Opponents gathered signatures for a veto referendum, which ordinarily would have suspended the law until the election. On October 2, 2024, Governor Healey signed an emergency preamble that took the law out of suspension and put it into immediate effect. The referendum itself appears on the November 3, 2026 ballot: a Yes vote keeps Chapter 135, and a No vote repeals it going forward. The pending vote changes nothing about present obligations. The law is in force now, a violation committed before the election is prosecuted under the law as it exists today, and a later repeal would not retroactively legalize conduct that occurred while the law was active. Waiting for November is not a compliance strategy. It is a plan to be a defendant.

Deadline One: Serialization by October 2, 2026

M.G.L. c. 140, § 121C requires that all firearms, with limited exemptions such as antique firearms, carry a serial number, and 501 CMR 20.00 sets October 2, 2026 as the compliance date for firearms already possessed when the requirement took effect. Because Chapter 135 expanded the definition of a firearm, the requirement reaches not only complete pistols, rifles, and shotguns but also frames, receivers, and unfinished frames or receivers, including 3D-printed frames and the 80 percent lowers sold for home completion. An owner of an unserialized firearm or frame complies in three steps: request a unique serial number from the Department of Criminal Justice Information Services through the state portal, have the number conspicuously and permanently engraved, cast, or embedded, and register the serialized firearm in the owner’s name.

After October 2, 2026, possession of a non-serialized firearm, frame, or receiver is a criminal offense complete on possession alone. The owner of a privately made firearm who has taken no steps by the deadline holds the highest exposure under the new framework, because there is no additional conduct the Commonwealth needs to prove.

Deadline Two: Portal Registration by October 28, 2026

Chapter 135 created a statewide electronic registration system under M.G.L. c. 140, § 121B. Going forward, registration runs on transaction timelines: a firearm acquired by purchase, private sale, or self-manufacture must be registered within 7 days of the transaction, a new resident must register the firearms brought into the Commonwealth within sixty days, and an heir who receives a firearm through an estate has sixty days to comply. For firearms already possessed before the portal came online in October 2025, EOPSS Guidance Letter #4 sets the administrative compliance date: those firearms must be registered through the portal by October 28, 2026. Firearms already recorded through the prior FA-10 transaction system do not need to be re-registered.

The two deadlines are cumulative for the owner of an unserialized firearm: the serial number must exist by October 2, and the registration must be complete by October 28. For the owner of a conventional, serialized firearm never recorded in the FA-10 system, only the October 28 registration applies. For an owner whose firearms all passed through Massachusetts dealers with FA-10 records, there may be nothing to do at all, but that conclusion should rest on checking the portal record, not on memory of paperwork from years ago.

The Grandfathering Rules

Two grandfather dates matter and are easy to confuse. Assault-style firearms lawfully possessed before August 1, 2024, including copies and duplicates of the models identified in the Attorney General’s July 20, 2016 enforcement notice, remain lawful to possess under § 131M. Large capacity feeding devices are grandfathered only if manufactured before September 13, 1994. Grandfathered status protects possession; it does not exempt the firearm from the serialization and registration requirements above, and it does not authorize carrying in the expanded prohibited areas. An owner asserting grandfathered status should hold documentation of when the firearm was acquired, because the burden of the conversation, at a licensing desk or at a hearing, falls in practice on the owner.

The Penalty Framework When Compliance Fails

The registration and serialization provisions sit on top of the existing penalty structure of M.G.L. c. 269, § 10, and a compliance failure often exposes an owner to more than one charge. Unlicensed carrying of a firearm under § 10(a) carries a mandatory minimum sentence of eighteen months, and after Commonwealth v. Guardado, 491 Mass. 666 (2023), the absence of a license is an element the Commonwealth must prove beyond a reasonable doubt rather than a defense the accused must raise. Possession of a firearm or ammunition without the required identification card is separately charged under § 10(h), and possession of a large capacity weapon or feeding device is charged under § 10(m). Improper storage is its own offense under M.G.L. c. 140, § 131L, which requires firearms to be secured in a locked container or equipped with a tamper-resistant lock when not under the owner’s control. Each statute stands alone, so a single police encounter over an unregistered firearm can produce a complaint application listing several counts. The charging decision belongs to the police and the clerk-magistrate, not to the owner’s sense of which violation seems technical.

The Prohibited Areas Problem

Carrying a firearm on school or college grounds has long been a separate offense under M.G.L. c. 269, § 10(j), which applies to elementary schools, secondary schools, and institutions of higher education, and reaches license holders unless the institution has given written authorization. Chapter 135 expanded the surrounding sensitive-places framework, adding locations such as government buildings where carrying is prohibited even with a valid license to carry. In Greater Boston the campus rule alone sweeps in the institutions that dominate Cambridge, Somerville, and parts of Boston. A licensed carrier who crosses onto university property with a firearm commits a separate offense unrelated to the registration deadlines, and these cases are appearing in the Boston Municipal Court and Cambridge District Court now, before the October deadlines arrive.

A Practical Compliance Checklist

The compliance work is documentary, and the documentation later becomes the defense file if anything goes wrong. Owners should work through the following before the deadlines, not in the final week.

Inventory everything. List every firearm, frame, receiver, and unfinished frame or receiver in your possession, with serial numbers where they exist. The expanded definition means the box of parts in the basement counts.

Check the portal record. Log into the state portal and confirm which firearms already appear from prior FA-10 filings. Do not assume a dealer purchase from years ago was recorded; verify it.

Serialize early. For anything without a serial number, request the number through the portal now. Engraving to the required depth takes a gunsmith appointment, and the final weeks before October 2 will be crowded.

Save every confirmation. Screenshot or print the portal confirmation for each serial number request and each registration. Dated proof of when you acted is the single most valuable document at any later hearing.

Mind transport during compliance. Moving an unserialized frame to a gunsmith or a firearm to a dealer must itself comply with the transport rules, unloaded and in a locked case under M.G.L. c. 140, § 131C. Do not create a carrying offense while curing a registration one.

Check your license scope. Chapter 135 redrew the line between what an FID card and an LTC each authorize. An FID holder who owns semiautomatic rifles or shotguns should confirm with counsel or the licensing officer whether the current license still covers what they own.

Heirs and new residents: calendar the sixty days. The inheritance and new-resident windows run from the event, not from when you learn about the rule.

If You Have Already Missed a Deadline or Received a Notice

An owner who discovers a compliance failure after the fact should speak with counsel before taking the firearm anywhere or making any statement to police or licensing officials. Walking an unserialized frame into a police station to ask what to do creates a documented admission of the completed offense. In most cases the violation can still be cured, and cured compliance is the strongest card at the hearing that follows, but the sequence in which it is cured matters, and that sequence is something to plan with counsel rather than improvise at a service window.

If a summons or show cause notice has already arrived, the case is at its most containable point and also its most dangerous one for the unrepresented. Anything said at the hearing can be used later if a complaint issues. See I Received a Show Cause Notice in Massachusetts. What Do I Do?

Why These Cases Start at the Clerk-Magistrate Hearing

Most Chapter 135 compliance violations involve previously lawful owners: license holders who missed a deadline, misread the assault-style features test, or did not know that an unfinished frame now counts as a firearm. Because these defendants are typically not arrested, the case usually begins with an application for a criminal complaint and a summons to a clerk-magistrate hearing under M.G.L. c. 218, § 35A. That hearing is the one stage at which the case can end with no complaint, no arraignment, and no CORI entry.

The hearing is private and informal. Hearsay is admitted, the police report is usually the entire showing, and there is no right to cross-examine, though the clerk-magistrate may permit questioning in their discretion. Eagle-Tribune Publishing Co. v. Clerk-Magistrate of the Lawrence Division, 448 Mass. 647 (2007). The clerk-magistrate applies a probable cause standard, Commonwealth v. DiBennadetto, 436 Mass. 310 (2002), and holds discretion to decline the complaint even where that standard is met. Bradford v. Knights, 427 Mass. 748 (1998). For the governing statutes and case law in full, see The Law of Clerk-Magistrate Hearings in Massachusetts.

The defense presentation at these hearings is documentary. The portal serial number request, the registration confirmation, the gunsmith invoice, the licensing history, and the absence of any prior record give the clerk-magistrate a concrete basis to conclude that a criminal complaint serves no purpose the completed compliance has not already served. An owner who corrected the violation before the hearing appears before the magistrate having eliminated the conduct at issue, and the genuine confusion produced by the emergency preamble, the portal rollout, and the pending referendum is itself part of the proportionality argument. Counsel also decides whether the client speaks at all, because the informality of the room does not change where statements travel afterward. For the full framework, see Do I Need a Lawyer for a Massachusetts Clerk-Magistrate Hearing?

Courts Where Serpa Law Office Defends Firearms Cases

A possession or compliance offense is charged where the possession occurred, which for most owners means the District Court or Boston Municipal Court division covering their home, and for carrying offenses the court covering the location of the stop. Serpa Law Office defends firearms charges and clerk-magistrate hearings in the following courts:

• Boston Municipal Court (all divisions, including Central, Brighton, Charlestown, Dorchester, East Boston, Roxbury, South Boston, and West Roxbury)
• Cambridge District Court
• Somerville District Court
• Newton District Court
• Brookline District Court
• Waltham District Court
• Malden District Court
• Woburn District Court
• Concord District Court
• Framingham District Court
• Dedham District Court
• Quincy District Court
• Hingham District Court
• For the full list, see Courts We Serve Across Greater Boston.

Key Takeaways

Two deadlines, not one: serialization of unserialized firearms, frames, and receivers by October 2, 2026 under 501 CMR 20.00, implementing M.G.L. c. 140, § 121C, and portal registration of already-possessed firearms by October 28, 2026 under EOPSS guidance. Firearms already recorded through the prior FA-10 system need not be re-registered.

Chapter 135 defines frames, receivers, and unfinished frames or receivers as firearms, so 80 percent lowers and printed frames fall under both deadlines.

Grandfathering (assault-style firearms lawfully possessed before August 1, 2024; large capacity feeding devices manufactured before September 13, 1994) protects possession but does not exempt serialization, registration, or the prohibited-areas rules.

The surrounding penalty framework is severe: unlicensed carrying under M.G.L. c. 269, § 10(a) carries an eighteen-month mandatory minimum, and licensure is an element the Commonwealth must prove. Commonwealth v. Guardado, 491 Mass. 666 (2023). Carrying on school or college grounds is separately criminal under § 10(j) even for license holders.

The November 3, 2026 referendum does not suspend the law, and a repeal would not retroactively legalize violations that occurred while the law was in force.

Save every portal confirmation; dated proof of compliance effort is the core of the defense file.

If you have missed a deadline or received a notice, speak with counsel before transporting anything or making any statement. Most compliance cases begin with a summons to a clerk-magistrate hearing, where documented good-faith compliance can end the case before any CORI entry exists.

Related Serpa Law Office resources

• Massachusetts Firearms Defense
• Clerk-Magistrate Hearings in Massachusetts
• The Law of Clerk-Magistrate Hearings in Massachusetts
• Do I Need a Lawyer for a Massachusetts Clerk-Magistrate Hearing?
• I Received a Show Cause Notice in Massachusetts. What Do I Do?
• A Practitioner’s Guide to Massachusetts Clerk-Magistrate Hearings
• Courts We Serve Across Greater Boston
• Arraignment in Massachusetts
• Massachusetts Criminal Records and CORI
• Illegal Searches and Seizures in Massachusetts
• Your Right to Remain Silent in Massachusetts
• Massachusetts Criminal Defense Results