Home-Build Rules by State: Seven Restrict, Nine Require Serialization

Building a firearm for yourself is lawful in most of the country and unserialized in most of the country. Seven states impose substantial restrictions. Those restrictions are not one felony rule, and the difference matters.

Here is the current dataset distribution across all fifty-one jurisdictions:

	Jurisdictions
Build allowed, no serial number required	34
Build allowed, serial number required	9
Build materially restricted	7
Requires a separate legal-status review	1 (Delaware)

The seven

Colorado. Two layers. C.R.S. 18-12-111.5, added in 2023, still says a person shall not manufacture a frame or receiver, including with a three-dimensional printer. The only exception in 18-12-111.5(5)(a)(II) is a federally licensed manufacturer. HB26-1144 then added a separate offense effective 1 July 2026: a first 3D-print offense is a class 1 misdemeanor, a subsequent offense a class 5 felony, with additional exemptions that include specified accredited gunsmithing instruction.

Cite it as 18-12-118, not 18-12-119. Section 1 of HB26-1144 says “add 18-12-119”, and a great many summaries repeat that, but the official Colorado Revised Statutes 2026 codified it at 18-12-118 — “Unlawful three-dimensional printing of a firearm or firearm component” — with an editor’s note recording the renumbering. There is no 18-12-119. A citation to the bill’s own section number points at nothing. The 2026 overlay does not repeal the older manufacture bar. Do not reduce Colorado to “FFL only,” and do not treat a class-build exemption as a general hobbyist path.

Hawaii. HRS § 134-10.2 makes it a Class C felony for anyone not holding an annual county-issued manufacturer license, and not a federal licensee, to possess or produce an unserialized receiver for the purpose of assembling a firearm — 3D printing named expressly.

Nevada. NRS 202.3635(1) bars manufacturing or assembling a firearm that does not bear a serial number, with narrow exceptions for inoperable firearms, antiques, and curios or relics. The first offense is a gross misdemeanor; a subsequent offense can be a Category D felony. “Assemble” is defined, which matters.

New Jersey. Four independent bars, the broadest being 2C:39-9(d) — manufacturing without being licensed under chapter 58 is a fourth-degree crime, with no personal-use exception — plus 2C:39-9(k), which reaches the purchase of parts with intent to assemble.

New York. Penal Law § 265.10(1) makes manufacturing a ghost gun or unfinished frame or receiver a Class D felony, with exemptions running to licensed gunsmiths and dealers only.

Rhode Island is the outlier and the strictest. § 11-47-8(e): “No person shall manufacture, sell, offer to sell, transfer, purchase, possess, or have under his or her control a ghost gun or an undetectable firearm or any firearm produced by a 3D printing process.” Up to ten years and $10,000. Read that last clause again — Rhode Island bans the process, not the absence of a serial number. A 3D-printed firearm that a licensed manufacturer serialized is still within the words of the statute; the only carve-out is for a Type 07 FFL.

Washington reaches possession of unfinished frames or receivers and manufacture by 3D printer or CNC machine through RCW 9.41.326 and related provisions. The first violation is a $500 civil infraction; later or aggregated conduct can escalate to misdemeanor or gross-misdemeanor treatment. It is not a uniform Class C/D felony rule.

The ten that let you build and want it numbered

California, Connecticut, the District of Columbia, Illinois, Maine, Maryland, Massachusetts, Minnesota, Oregon and Vermont permit self-manufacture and require a serial number on the result — generally one applied by a licensee.

Two are worth flagging, because they are the group’s only full constitutional-carry states: Vermont and Maine.

Vermont’s Ghost Guns Act took effect on 28 February 2025. Maine’s requirement is newer and arrived quietly: P.L. 2025 ch. 537 became law without the Governor’s signature on 11 January 2026, enacting 25 M.R.S. ch. 253-A. The two are not yet equivalent — Maine defers penalties to 1 January 2027, while Vermont’s is enforceable today.

Maine is also a caution about this whole subject. Our own August 2026 research put Maine in the no-serialization column, because the official statute site was serving text current only through 5 January 2026 — six days before the act became law. Both requirements are recent enough that a large share of published building guides still describe these states as unrestricted. We wrote about the inversion separately in Vermont Is the Freest State to Carry, and the Worst to Carry From.

Delaware, and Rigby v. Jennings

Delaware’s current code at 11 Del. C. § 1463 makes manufacturing an untraceable firearm a Class D felony, possession a Class E felony, and 3D-printed production without a manufacturer’s license a Class D felony. Subsection (c)(2) also criminalizes distributing the files. Section 1459A separately reaches unfinished frames and receivers.

That is no longer the operative picture, and the change is five days old at the time of writing. In Rigby v. Jennings, C.A. No. 21-1523-MN (D. Del.), Judge Maryellen Noreika entered a memorandum opinion, an order on the cross-motions for summary judgment, and final judgment closing the case, all on 10 September 2026 (D.I. 81, 82 and 83). The 2022 preliminary injunction — and the “cross-motions still pending” posture that every summary of this case has been carrying, including our own until today — is superseded.

Permanently enjoined: § 1459A(b), § 1463(a), § 1463(c)(1), and the manufacture and assembly prongs of § 1463(b). Note that § 1463(c)(1) is the 3D-printing provision, so that prohibition is enjoined and not merely paused.

Declared constitutional and enforceable: § 1459A(a), the sell-and-transfer prong of § 1463(b), and § 1463(c)(2), the file-distribution provision.

The practical effect is that Delaware moves out of the restricted group in our data: building for personal use is lawful there and no state serial number is required, while selling, transferring or distributing files remains a crime. That is close to the opposite of how most published guides still describe Delaware, and our own classification said selfManufactureAllowed: null until this verification.

One caveat that matters: as of 15 September 2026 no notice of appeal appeared on the docket, but the thirty-day window was still open. A Third Circuit appeal would not revive the enjoined provisions on its own, but anyone relying on this should check whether one has been filed.

The two cases that have already been decided

Both of them lost, and pretending otherwise would be useless to anyone planning around them.

Defense Distributed v. Attorney General New Jersey (Third Circuit). Defense Distributed and the Second Amendment Foundation challenged New Jersey’s cease-and-desist letter and its 2018 statute criminalising distribution of 3D-printing files to unlicensed residents, arguing the measures burdened the distribution of computer code. The Third Circuit affirmed dismissal with prejudice, holding that purely functional code with no actual or intended expressive use is not covered by the First Amendment, and that the complaint neither identified which files the statute reaches nor pleaded facts showing the code is expressive. The plaintiffs had declined an opportunity to amend — a detail worth sitting with, because the holding is narrower than the headline and turns substantially on the pleading.

Sisolak v. Polymer80 (Nevada Supreme Court, decided 18 April 2024). Polymer80 won a permanent injunction in the district court on vagueness grounds. The Nevada Supreme Court reversed, holding that “unfinished frame or receiver” uses terms with ordinary meanings, that the offences are general-intent crimes requiring proof the defendant knew the object’s characteristics, and that they do not invite arbitrary enforcement.

Both are in the case tracker with the full opinion text.

The federal layer, which is where this gets dangerous

Everything above is state law. For an ordinary rifle or pistol built for your own use, that is genuinely the whole picture on serialization: federal law imposes no marking requirement on a non-licensee making a Title I firearm for personal use, which is exactly why the state answer decides the question and why this map is worth having.

For an NFA item it is the reverse, and the state answer barely matters. Suppressors, short-barreled rifles, short-barreled shotguns and AOWs are governed by 26 U.S.C. § 5842(a), which requires a maker to identify what they make with a serial number, and § 5861(i), which makes possessing a firearm that is not so identified an offence carrying up to ten years. Live in one of the thirty-four states above and build a suppressor in your garage, and you have complied with your state and committed a federal felony.

That layer moved on 12 August 2026, and it moved for some people and not others. The judgment in Silencer Shop Foundation v. ATF resolved two consolidated cases that did not win the same relief:

	Making approval (§ 5822)	Marking (§ 5842(b), § 5861(i))
Jensen plaintiffs — TSRA, CCRKBA, FPC Action Foundation, Hot Shots Custom	Enjoined	Enjoined
Silencer Shop plaintiffs — GOA, FRAC, Silencer Shop, PSA, SilencerCo, B&T, 15 states	Enjoined	Not enjoined
Everyone else	Applies in full	Applies in full

The marking challenge was the Jensen side’s, and only the Jensen side won it. The practical result is the opposite of what most people assume from which organisation has publicised this ruling loudest: a GOA membership lets you skip the Form 1 and still leaves you owing a serial number, and possessing an unmarked one is its own felony under § 5861(i). A CCRKBA or TSRA membership reaches the marking relief. Residency in a plaintiff state reaches nothing.

We have set the whole thing out, including who is covered and the transport traps that catch people afterwards, in what the NFA ruling actually lets you do. If you are reading this page because you intend to build a can rather than a rifle, read that one instead — this map will not answer your question.

What this article is not

This is state law only, except for the federal section immediately above. Federal law otherwise applies independently and is not covered here — a state that requires nothing of you still leaves the federal layer entirely intact, and the two do not cancel out.

The map is date-sensitive, and one entry on it has a known expiry. New York Penal Law § 265.10(1) currently makes manufacturing a ghost gun or unfinished frame or receiver a Class D felony. A rewritten § 265.10 takes effect on 25 August 2026, adding convertible-pistol and digital-firearm-code offenses. This article states the law in force on 14 August 2026, so the New York paragraph above has eleven days of shelf life from publication. On or after the 25th, read the new text rather than this description of the old one.

We do not host designs, files, or build instructions, and nothing above is advice about whether to build anything. It is a map of where the state lines fall, which is the thing that is genuinely hard to look up and genuinely easy to get wrong. Vermont’s requirement is eighteen months old and Maine’s is eight; a guide written in 2024 is wrong about Vermont, and one written in 2025 is wrong about Maine.

Per-state detail with the statute behind each classification is on the state guides, and the organisations doing the legal work in this area are listed on our building page.