Owning a 15-round magazine in California is illegal for most people. State law defines any ammunition feeding device that can accept more than 10 rounds as a “large-capacity magazine,” so a standard 15-round pistol magazine falls squarely inside the prohibition. Buying, selling, or bringing one into the state has been a crime for years. Whether you can keep one you already own is the piece that has been fought over in court, and a March 2025 Ninth Circuit ruling upheld the ban with a petition now pending before the U.S. Supreme Court.
Why 15 Rounds Crosses the Line
California Penal Code Section 16740 sets the threshold at 10. Any feeding device that can accept more than 10 rounds is a large-capacity magazine, whether it holds 11, 15, or 30.1California Legislative Information. California Code 16740 – Definition of Large-Capacity Magazine Three narrow carve-outs exist: a feeding device permanently altered so it cannot hold more than 10 rounds, a .22 caliber tube feeding device, and a tubular magazine contained in a lever-action firearm.2California Legislative Information. California Code PEN 16740 – Definitions
The word doing the work is “capacity.” A magazine built to hold 15 rounds is a large-capacity magazine even if you only load 10 into it. The law looks at what the device can accept, not what you choose to put in it.
What Is Banned, and What Is Still Being Litigated
Penal Code Section 32310 creates two separate prohibitions, and they have very different legal histories.
Subsection (a) bans manufacturing, importing, selling, buying, lending, and giving away any large-capacity magazine. This has been continuously enforceable. No court order has ever paused it. If you buy a 15-round magazine, sell one, or drive across the state line with one today, you are committing a crime under this provision.3California Legislative Information. California Penal Code 32310
Subsection (c), added by Proposition 63 in 2016 and effective July 1, 2017, went further. It bans mere possession regardless of when the magazine was acquired. That provision is the one that has been enjoined, litigated, and appealed for years, and the one that decides whether you can keep a 15-round magazine already sitting in your safe.
Where Duncan v. Bonta Stands
The possession ban has been contested in Duncan v. Bonta since 2017. In March 2019, a federal district court struck the statute down. The judge later partially stayed his own order, leaving the possession ban enjoined while appeals played out.
On March 20, 2025, a Ninth Circuit en banc panel reversed the district court and upheld California’s large-capacity magazine ban against the Second Amendment challenge.4United States Court of Appeals for the Ninth Circuit. Duncan v. Bonta The court remanded with instructions to enter judgment for California’s Attorney General. A petition for certiorari was filed with the U.S. Supreme Court on August 15, 2025, docketed as No. 25-198.5SCOTUSblog. Duncan v. Bonta (25-198)
Whether the possession piece is actively enforceable at any given moment depends on whether a stay is in place. Check the current status of the case before relying on any specific answer about possession. The acquisition prohibitions in subsection (a) are not affected by any of this and remain in force.
Freedom Week and Pre-2000 Magazines
Between March 29 and 5:00 p.m. on April 5, 2019, the district court’s ruling created a brief window, widely called “Freedom Week,” during which Californians could lawfully buy large-capacity magazines. Thousands did. Judge Benitez’s April 4, 2019 order preserved protections for people who manufactured, imported, sold, or bought magazines holding more than 10 rounds during that window.
Those protections came from the district court’s injunction. The Ninth Circuit’s en banc reversal undermined the legal foundation for them. If the Supreme Court declines the case or ultimately upholds the ban, Freedom Week magazines lose their safe harbor and possessing them becomes a criminal offense under Section 32310(c).3California Legislative Information. California Penal Code 32310
The same reasoning applies to magazines owned before California’s original ban took effect on January 1, 2000. Section 32310(c) prohibits possession “regardless of the date the magazine was acquired.” Section 32420 does allow someone who lawfully owned a magazine before January 1, 2000, took it out of state, and returned with the same magazine to avoid violating the import prohibition, but that narrow exception does not override the possession ban itself.6Justia. California Penal Code – Article 2 Exceptions Relating Specifically to Large-Capacity Magazines
Who Is Actually Exempt
The exemptions in Penal Code Sections 32400 through 32450 are narrow and tied to job function.
- Law enforcement agencies at the federal, state, and local level, with employees permitted to possess large-capacity magazines for official duties when the agency authorizes it.7California Legislative Information. California Code PEN 32400 – Exceptions Relating Specifically to Large-Capacity Magazines
- Active sworn peace officers authorized to carry a firearm in the course of their duties, covering sale, purchase, possession, lending, and import.8California Legislative Information. California Penal Code 32405
- Honorably retired sworn peace officers and retired federal law enforcement officers, exempted from the possession ban but not from the prohibitions on buying or importing.9California Legislative Information. California Code, Penal Code – PEN 32406
- Holders of a special weapons permit, who may purchase large-capacity magazines for use as film and television props, for export, or for resale to law enforcement and military agencies.6Justia. California Penal Code – Article 2 Exceptions Relating Specifically to Large-Capacity Magazines
There is no broad personal-use exemption for individual service members living in California off duty. Section 32440 permits manufacturing large-capacity magazines for military use, and Section 32400 covers military agencies the same way it covers law enforcement agencies, but those provisions run to the agency and the manufacturing purpose, not to personal possession.
Penalties
The consequences depend on which part of Section 32310 you violate. Prosecutors treat manufacturing, importing, and selling far more seriously than simple possession.
A violation of Section 32310(a) is a wobbler. Charged as a misdemeanor, it carries up to one year in county jail. Charged as a felony, it carries 16 months, two years, or three years in county jail under Section 1170(h).3California Legislative Information. California Penal Code 3231010California Legislative Information. California Penal Code 1170 A felony conviction means a permanent criminal record and the loss of firearm rights.
Possession under Section 32310(c), once enforceable, is treated less harshly. It can be charged as an infraction with a fine of up to $100 per magazine, or as a misdemeanor carrying up to $100 per magazine in fines, up to one year in county jail, or both.11California Legislative Information. California Code PEN 32310 – Large-Capacity Magazine The per-magazine structure means owning several prohibited magazines multiplies the fine.
What to Do If You Already Own One
If the possession ban becomes fully enforceable and you are not exempt, Section 32310(d) gives you three legal options: remove the magazine from California, sell it to a licensed firearms dealer, or surrender it to law enforcement for destruction.3California Legislative Information. California Penal Code 32310
A fourth option exists inside the definition itself. Section 16740 excludes any feeding device permanently altered so it cannot accept more than 10 rounds. California’s Department of Justice has published regulations describing acceptable modification methods, which involve inserting a rigid magazine block and then permanently securing it with epoxy and rivets so the floor plate cannot be removed.12California Department of Justice. Text of Regulations – Large-Capacity Magazine Permits The critical word is “permanently.” A removable block or a pin you can punch out does not satisfy the standard.
Bringing One In From Another State
No federal law restricts magazine capacity. The federal assault weapons ban that included a large-capacity magazine provision expired in 2004 and has not been renewed. Magazine limits exist only at the state level, and California’s 10-round line is among the most restrictive in the country.
The rules change the instant you cross into California. A 15-round magazine legal in Nevada or Arizona becomes contraband the moment it enters the state. Travelers passing through get no exemption from the import prohibition, and driving through with a prohibited magazine in your vehicle counts as importing it.
Flying does not change the analysis. Federal TSA rules let you transport magazines and ammunition in checked baggage if the firearm is unloaded, locked in a hard-sided container, and declared at the ticket counter.13Transportation Security Administration. Transporting Firearms and Ammunition Those rules govern the flight. The moment you land and claim your bags, you are subject to the law of whatever state you are in. Landing at a California airport with a 15-round magazine in checked luggage is importing a prohibited item into California, regardless of how carefully it was packed.