Owning a firearm built from an 80% lower receiver is legal in Texas for any adult who isn’t federally or state-prohibited from having a gun, and Texas adds no restrictions beyond federal law. What changed recently is what counts as an “80% lower” in the first place: a 2022 ATF rule, upheld by the Supreme Court in March 2025, pulled many partially finished frames and parts kits into the same regulatory category as finished firearms.
What the 2022 ATF Rule Changed
For years, an 80% lower was treated as raw material. You could order one online, no background check, no serial number, no paperwork. ATF Rule 2021R-05F took effect on August 24, 2022, and rewrote the definitions of “frame or receiver” and “firearm” for the first time in decades.
Under the updated rule, a partially complete frame or receiver that can be “readily” converted into a functional one now counts as a regulated frame or receiver. The ATF weighs factors like the time, tools, and expertise required to finish the part. The rule also expanded the definition of “firearm” to cover parts kits that bundle an unfinished frame or receiver with the jigs, templates, or tools needed to complete it. Kits like that must be serialized and sold through licensed dealers who run background checks.1Bureau of Alcohol, Tobacco, Firearms and Explosives. Summary of Final Rule 2021R-05F
The rule did not ban 80% lowers. A blank piece of aluminum or polymer that hasn’t been machined far enough to be readily completed remains unregulated. The line now runs between “raw material” and “readily convertible,” and the marketing label on the product doesn’t decide which side a given part falls on.
The Supreme Court Upheld the Rule in 2025
Manufacturers and gun-rights groups sued. The case reached the Supreme Court as Bondi v. VanDerStok, and on March 26, 2025, the Court reversed the Fifth Circuit in a 7–2 decision. Justice Gorsuch, writing for the majority, held that the ATF rule is “not facially inconsistent” with the Gun Control Act, and that terms like “weapon,” “frame,” and “receiver” can describe unfinished objects when their intended function is clear. Because the statute “plainly reaches some partially complete items,” the blanket challenge failed.2Supreme Court of the United States. Bondi v VanDerStok, No 23-852
The practical result: the rule stands. Parts kits sold with the jigs and instructions that make completion straightforward are firearms. The seller must be licensed, the frame or receiver must carry a serial number, and the buyer must pass a background check. A bare 80% lower sold without completion tools falls into a grayer zone where the “readily convertible” test applies part by part.
What Texas Adds
Nothing, essentially. Texas has no statute that specifically addresses unfinished frames or receivers, and no state-level serialization or registration requirement for a firearm you build for your own use. There is no state permit or license to buy a rifle, shotgun, or handgun.
Texas also does not require private sales between individuals to run through a licensed dealer. So if federal law doesn’t force a particular transaction through an FFL, Texas won’t either. That said, the federal restrictions below still bind you inside Texas.
Who Cannot Build or Possess One
The right to build a firearm for personal use only exists if you can lawfully possess one. Federal law bars several categories of people from possessing any firearm or ammunition, and that ban applies just as much to a home-built gun as to a store-bought one. Prohibited persons include anyone who:3Bureau of Alcohol, Tobacco, Firearms and Explosives. Identify Prohibited Persons
- Has been convicted of any crime punishable by more than one year in prison
- Is a fugitive from justice
- Is an unlawful user of, or addicted to, a controlled substance
- Has been adjudicated mentally defective or committed to a mental institution
- Is in the country without lawful immigration status
- Was dishonorably discharged from the military
- Has renounced U.S. citizenship
- Is subject to a qualifying protective order involving an intimate partner or that partner’s child
- Has been convicted of a misdemeanor crime of domestic violence
Texas layers its own penalties on top. Under Texas Penal Code Section 46.04, a convicted felon who possesses a firearm commits a third-degree felony during the first five years after release from confinement, parole, or supervision. After that five-year window, a felon may possess a firearm only at their own home. Someone convicted of a Class A misdemeanor involving family violence is barred from possessing a firearm for five years after release, and possessing a firearm while subject to a qualifying protective order is itself a Class A misdemeanor.4State of Texas. Texas Penal Code 46.04 – Unlawful Possession of Firearm
The absence of a background check at purchase doesn’t create a safe harbor. The offense is possession. A prohibited person who finishes an 80% lower faces the same exposure as one caught with any other gun.
Age Limits
Federal law sets 18 as the minimum age to possess a long gun and 21 to buy a handgun from a licensed dealer. Because a completed AR-15 lower can be built into either a rifle or a pistol, the intended configuration matters. Texas sets 21 as the general age to carry a handgun, though a 2022 federal court ruling found that Texas cannot prosecute 18-to-20-year-olds solely based on age for handgun carry.5Texas State Law Library. Carry of Firearms – Gun Laws Texas does not impose a minimum age for possessing a long gun, but the federal dealer restrictions still apply at the point of sale.
NFA Configurations Still Require Approval
Building a gun for personal use does not exempt you from the National Firearms Act. If the finished build falls into an NFA category, you need ATF approval before you start machining. The common traps for 80% lower builders are short-barreled rifles (a rifle with a barrel under 16 inches or an overall length under 26 inches) and short-barreled shotguns.
As of January 1, 2026, the $200 NFA tax stamp is eliminated for suppressors, short-barreled rifles, short-barreled shotguns, and “any other weapons,” but you still must submit the application and pass a background check before taking possession. The $200 tax remains in effect for machine guns and destructive devices. Building an unregistered machine gun, meaning a firearm that fires more than one round per trigger pull, is a federal felony regardless of intent to keep it for personal use.
Serial Numbers and Selling What You Build
If you finish an 80% lower and keep it for yourself, federal law does not require you to add a serial number. The ATF’s guidance states plainly: “You do not have to add a serial number or register the PMF if you are not engaged in the business of making firearms for livelihood or profit.”6Bureau of Alcohol, Tobacco, Firearms and Explosives. Privately Made Firearms
Serialization becomes mandatory the moment a privately made firearm passes through a licensed dealer. If you send yours through an FFL for sale or transfer, the dealer must engrave a serial number on the frame or receiver within seven days of receiving it or before transferring it, whichever comes first. The number uses the dealer’s abbreviated license number as a prefix, must be engraved at least 0.003 inches deep, and must appear in a print size no smaller than 1/16 inch.7eCFR. 27 CFR 478.92 – Identification of Firearms and Armor Piercing Ammunition
Texas does not require private individual-to-individual sales to run through an FFL, so a Texas resident could privately sell a personally made firearm without adding a serial number. The seller still cannot transfer to a prohibited person. And anyone who builds firearms with the intent to sell them, rather than occasionally parting with a personal gun, crosses into “engaged in the business” territory. That requires a federal firearms license, and doing it without one carries up to five years in prison and a fine of up to $250,000.8Bureau of Alcohol, Tobacco, Firearms and Explosives. Do I Need a License to Buy and Sell Firearms
One more thing worth knowing: the second you finish machining the lower, it is a firearm under federal law. Every rule that applies to a commercially manufactured gun applies to yours from that point on, including the possession bars and the NFA configuration limits above.9Bureau of Alcohol, Tobacco, Firearms and Explosives. Definition of Frame or Receiver and Identification of Firearms