What Are Ghost Guns and 3D Printed Firearms Under Massachusetts 2026 Laws?

Ghost guns are unserialized, privately manufactured firearms (PMFs) that include unfinished frames, receivers, and kits, and they’re now treated as contraband under M.G.L. c. 140 § 121.

• Visual Aid Requirement: A diagram showing the difference between a “frame” (pistol) and “receiver” (rifle). Purpose: To clarify the new broader definitions and distinguishing “readily convertible” parts.

Under the 2026 legal framework, a ghost gun is any firearm or “readily convertible” unfinished frame or receiver that lacks a unique, state-assigned serial number. A 3D-printed firearm is treated the same way unless you embed a compliant metal plate for serialization (more on that below). 

What You Need to Know

• An unfinished frame is considered a firearm if it’s readily convertible into a functional weapon.
  
• A ghost gun is a firearm with no unique serial number and is legally untraceable.
  
• A 3D-printed firearm is a polymer firearm created with additive manufacturing (3D printing), but is legally required to include a metal serialization plate.

• Not all weapons are affected. Antique firearms manufactured before 1899, and certain black powder weapons, are excluded, so hobbyists aren’t criminally liable. 

For information on licensing requirements, see our guide on gun possession charges.

How Have Massachusetts Ghost Gun Laws Changed in 2024-2025?

Massachusetts laws changed a lot with the Act Modernizing Firearms Laws (Chapter 135), effective October 2, 2024.

The Emergency Preamble accelerated enforcement, bypassing standard legislative waiting periods. The legislation expanded the definition of “firearm” to include kits, unfinished frames/receivers, and 3D-printed guns.

Additionally, M.G.L. c. 140 § 121E requires all owners to report serialized firearms to the DCJIS, with the Data Dashboard publicizing compliance rates. 

In our experience, Worcester County gun owners often forget that the Commonwealth’s improper storage laws apply to storage violations for ghost guns, too.

What Are the Penalties for Possessing Untraceable Firearms in MA?

Possessing an untraceable firearm is a felony, punishable under M.G.L. c. 269 § 10 by up to 10 years in state prison, with mandatory minimums of 18 months in certain cases.

If you’re accused of selling, distributing, or transferring an unserialized gun, the Commonwealth can elevate the case to trafficking, which carries even harsher penalties. If you have prior firearms convictions, you’re also at risk of habitual offender enhancements, which can impose the longest-range maximums.

For more on ACCA enhancement rules, read our guide on habitual offender laws.

How Do Serialization Requirements Apply to Existing Ghost Guns?

Existing ghost guns have to be serialized through the DCJIS electronic system (officially launched on August 1, 2025), and you’re required to complete serialization no later than October 2, 2026.

This is a hard regulatory deadline. There’s no leeway here. Every unserialized firearm or “readily convertible” frame/receiver has to be marked before October 2, 2026. New ghost guns brought into Massachusetts have been reported within 7 days of possession.

Special Requirements for 3D-Printed Firearms: If you’ve created a polymer firearm using PLA+, nylon, carbon fiber, or other filaments, the law requires you to embed a 3-ounce stainless steel plate so the serial number can be permanently engraved. Putting the serial number on the polymer/carbon fiber/filament isn’t enough.

• Visual Aid Requirement: A diagram showing where the 3-ounce plate must be embedded in a polymer frame to meet Massachusetts’ laser-engraving requirements.

If serialization issues have already triggered licensing problems, review our guide to LTC suspensions.

What Defenses Exist for Ghost Gun Charges in Massachusetts?

You can defend against ghost gun charges by challenging convertibility, the legality of the search, or the statutory timeline relating to Chapter 135.

• “Readily Convertible” Challenge: This defense argues that the seized item was not sufficiently complete to function or be converted into a firearm.
  
• Fourth Amendment Violations: If your Fourth Amendment rights were violated by a warrantless home entry or vehicle search, the evidence may be suppressed.
  
• Grandfathering/Timeline Audit: You can also defend against charges by showing that you possessed or created the ghost gun before Chapter 135’s effective date.
  

If your case involves a questionable search or seizure, you can find answers in our illegal search guide.

How Can 3D Printing and CNC Machines Lead to Gun Charges?

Using 3D printers, CNC/Ghost Gunner mills, or even specific CAD files can be considered evidence of “intent to manufacture” under M.G.L. c. 140 § 122D, even if the firearm never becomes functional.

Materials and Tools Prosecutors Focus On

• PLA+, nylon, carbon fiber filaments
• Ghost Gunner/CNC mills and metal jigs
• Slicer software and G-Code toolpaths
• Blueprints/CAD files for regulated frames and receivers
  

Prosecutors claim that the combination of materials and digital plans shows that you had “intent”. For help defending “intent” allegations, learn more about viable trafficking defenses.