Mexico Gun Laws for Americans: Complete Federal Firearms Crime Directory

For many Californians, owning a firearm is perfectly lawful. A person may legally buy a handgun, keep it at home, transport it under California rules, go to a shooting range, or obtain a concealed carry permit if all state and local requirements are satisfied.

The moment that person crosses into Mexico, however, the legal landscape changes completely.

Here is the bottom line: a California firearm registration, concealed carry permit, hunting license, or lawfully issued U.S. firearms document does not, by itself, authorize possession, carrying, transportation, or entry of that firearm into Mexico. Mexican law generally requires Mexican licenses or permits issued by the appropriate Mexican authority. For ordinary travelers, a U.S. permit does not substitute for those requirements.

This becomes especially dangerous at border crossings connecting California and Baja California. A driver may take the wrong lane, miss the final U-turn, or forget that a handgun, magazine, box of ammunition, or firearm component remains inside a truck, glove box, center console, range bag, trailer, backpack, or suitcase.

What may look like an honest mistake can still trigger a federal criminal investigation in Mexico.

Mexico’s Federal Firearms and Explosives Law does not create just one generic “gun crime.” It creates numerous separate offenses involving carrying, possession, transportation, importation, sale, acquisition, modification, manufacture, shipping, ammunition, magazines, gun parts, digital files, conversion devices, armored vehicles, explosives, and improvised explosive devices.

The following is a plain-English directory of the criminal conduct covered by Articles 81 through 89 Bis of Mexico’s current Federal Firearms and Explosives Law.

Legal notice: This guide is general educational information. The exact charge, penalty, jurisdiction, available defenses, and pretrial consequences depend on the firearm or object involved, its caliber and classification, the place where it was found, the person’s knowledge and control, the arrest report, customs evidence, forensic testing, and the facts of the border crossing.

Mexico Gun Laws: Key terms Americans need to understand

Before reviewing the directory, it is important to distinguish the major actions prohibited by the statute.

Carrying, generally translated from portación, usually involves having a weapon immediately available or within a person’s sphere of control outside the location where possession may be authorized.

Possession, or posesión, may involve keeping or controlling a firearm, ammunition, magazine, component, or explosive, even when it is not physically carried on the person.

Transportation is a separate act. A firearm locked in a vehicle, truck, RV, trailer, suitcase, or shipping container may still create a transportation allegation.

Introduction into Mexico generally refers to bringing, causing to be brought, or participating in bringing a regulated item into Mexican territory without the required authorization.

Commercialization, transfer, acquisition, or sale can each be treated as separate criminal conduct. A person does not necessarily have to be accused of being a large-scale trafficker to face a commercial-transfer offense.

Article 81: Carrying an otherwise permitted firearm without a Mexican license

Article 81 criminalizes carrying a firearm included within Articles 9 or 10 without the corresponding license.

These are generally firearms that may be legally permitted in Mexico under specified circumstances, but that does not mean they may be freely carried.

The identifiable conduct is:

1. Carrying a permitted handgun without a Mexican carry license.
2. Carrying a permitted rifle or sporting firearm without the required license.
3. Carrying two or more unlicensed firearms, which increases the applicable penalty.

The basic sentencing range is three to eight years in prison, plus a fine. Carrying two or more weapons may increase the sentence by as much as two-thirds.

For an American traveler, this means that saying, “The gun is legal back home,” does not resolve the Mexican charge. The central issue is whether Mexican law authorized the carrying of that specific weapon.

Article 81 Bis: Modifying or altering a firearm

Article 81 Bis punishes any person who performs a modification or alteration of a firearm.

The separate conduct includes:

4. Modifying a firearm.
5. Alter­ing a firearm’s original configuration or characteristics.

The punishment depends on the firearm category:

• Modifying certain reserved weapons under Article 11(a) or 11(b): four to six years.
• Modifying other weapons covered by Article 11: six to eight years.
• Modifying firearms covered by Articles 9 and 10: two to four years.

This provision can potentially reach alterations to operating mechanisms, caliber, configuration, essential parts, or other original characteristics, depending on the evidence and the expert examination of the firearm.

Article 82: Transferring firearm ownership without authorization

Article 82 addresses the unauthorized transfer of ownership.

The prohibited conduct includes:

6. Transferring ownership of one firearm without the required permit.
7. Transferring ownership of two or more firearms without permission.
8. Repeating an unauthorized firearm-transfer offense.

The ordinary penalty is one to six years. Transferring two or more firearms, or repeating the conduct, carries a range of five to fifteen years.

The transfer does not have to look like a retail gun-store transaction. Depending on the facts, it could involve a sale, exchange, gift, assignment, delivery, or another transaction intended to change legal ownership.

Article 82 Bis: Military personnel using personally owned firearms for private work

Article 82 Bis applies specifically to Mexican military personnel. It punishes a service member who violates the final paragraph of Article 24.

The underlying conduct is:

9. A military member carrying a personally owned firearm while providing services to a private security company or private individual without the required Defense or Navy authorization.

The penalty is six months to one year in prison or a fine.

This offense is unlikely to apply to an ordinary U.S. tourist, but it belongs in a complete directory of the statute.

Article 83: Carrying weapons reserved for Mexico’s Armed Forces

Article 83 is one of the most serious and frequently litigated sections of the law. It punishes carrying a weapon reserved for the exclusive use of Mexico’s Permanent Armed Forces without a valid license.

The prohibited or aggravating conduct includes:

10. Carrying an exclusive-use firearm without a valid Mexican license.
11. Carrying two or more exclusive-use firearms.
12. Possessing certain high-level reserved weapons as part of a group of three or more people.
13. Carrying those weapons as part of a group of three or more people.
14. Employing or using those weapons as part of a group of three or more people.
15. Using specified reserved weapons against legally constituted authorities.

Depending on the statutory classification, the punishment can range from three months to one year at the lowest level to twenty to thirty years for the most heavily restricted categories.

The presence of two or more weapons may increase the sentence. Group possession, carrying, or use may increase the sentence by two-thirds or up to twice the basic penalty. Using specified weapons against government authorities can produce an even more severe increase.

This is why the exact caliber, operating system, firearm type, and statutory classification matter. A prosecutor cannot simply call every gun a “military weapon” without connecting it to the categories established by the law.

Article 83 Bis: Stockpiling more than five firearms

Article 83 Bis addresses acopio, commonly understood as stockpiling or accumulating firearms.

The conduct includes:

16. Stockpiling and possessing more than five Armed Forces–reserved firearms without authorization.
17. Possessing more than five otherwise permitted firearms without the corresponding permit.

Penalties vary by firearm classification:

• Certain exclusive-use firearms: six to nine years.
• Higher-level exclusive-use categories: seven to thirty years.
• Certain firearms under Article 11(i): one to three years.
• More than five permitted firearms: generally one to four years or one to seven years, depending on the category.

The judge must consider the accused person’s occupation, criminal background, and the circumstances of the arrest when sentencing carrying or stockpiling offenses.

Article 83 Ter: Possession of exclusive-use firearms, components, or explosives

Article 83 Ter is primarily a possession statute.

The separate conduct includes:

18. Possessing an Armed Forces–reserved firearm without authorization.
19. Possessing essential parts of a reserved firearm.
20. Possessing components of a reserved firearm.
21. Possessing ammunition or cartridges falling within specified reserved categories.
22. Possessing any amount of explosive material without authorization.

The firearms-related penalties range from three months to one year through six to fifteen years, depending on classification.

Possessing any quantity of explosive material without the proper permit is punished under the same range used for the provision’s third category, which carries five to twelve years.

A major issue in these cases is whether the accused knowingly possessed the item and whether the object legally qualifies as an essential firearm part, component, ammunition, cartridge, or explosive under the statute.

Article 83 Quáter: Excess ammunition or cartridges

Article 83 Quáter covers quantities of ammunition or cartridges exceeding the limits established by Article 50.

The law identifies three separate actions:

23. Possessing ammunition or cartridges over the legal quantity.
24. Carrying ammunition or cartridges over the legal quantity.
25. Transporting ammunition or cartridges over the legal quantity.

The penalty is generally:

• One to four years for ammunition associated with the lower statutory firearm categories.
• Four to seven years for ammunition related to the remaining Article 11 categories.

An American can therefore be arrested even when no firearm is discovered. A box of cartridges, loose rounds, or ammunition left in a range bag may create a separate federal allegation.

Article 83 Quinquies: Magazines and ammunition-feeding accessories

Article 83 Quinquies specifically regulates magazines and other accessories used to feed ammunition into weapons reserved for the Armed Forces.

The separate conduct includes:

26. Possessing regulated magazines or feeding accessories.
27. Carrying regulated magazines or feeding accessories.
28. Transporting regulated magazines or feeding accessories.

The quantity affects the potential sentence:

• Two to five magazines or accessories: two to four years.
• More than five: four to eight years.

The magazine charge may be imposed separately from another firearms charge under the circumstances described in the statute.

For travelers, this means an empty magazine is not necessarily harmless merely because the corresponding firearm is not in the vehicle.

Article 83 Sexies: Digital gun files, conversion devices, and tactical accessories

Article 83 Sexies was added in the 2025 reform. It carries four to eight years in prison, plus a substantial fine.

It punishes the unlawful use or distribution of several categories of material.

Digital manufacturing information

29. Unlawfully using firearm designs.
30. Distributing firearm designs.
31. Using or distributing digital blueprints.
32. Using or distributing firearm-manufacturing instructions or manuals.
33. Using or distributing software intended to manufacture firearms, magazines, parts, or components.
34. Using or distributing machines intended for that manufacturing process.

Automatic-fire conversion devices

35. Using a device intended to convert a semiautomatic weapon into an automatic weapon.
36. Distributing a conversion device.
37. Using or distributing devices manufactured through additive, three-dimensional, or homemade methods.

Night-vision, laser, holographic, and thermal equipment

38. Unlawfully using night-vision equipment in the prohibited context.
39. Distributing night-vision equipment in that context.
40. Using or distributing laser designators.
41. Using or distributing holographic sights.
42. Using or distributing thermal sights.
43. Using or distributing other accessories intended to enhance weapon use outside recreational hunting or target shooting.

The wording of this article is broad, and each case requires careful analysis of the item, its purpose, the alleged activity, and whether the prosecution can prove unlawful use or distribution.

Article 83 Septies: Armored and weapon-adapted vehicles

Mexican gun laws: 7 main points you need to know

This article also came from the 2025 reform.

The conduct includes:

44. Using a military-type armored vehicle covered by Article 11.
45. Using a privately owned vehicle modified with armor and adapted for weapons.
46. Manufacturing an armored or weapon-adapted vehicle without authorization.
47. Assembling such a vehicle without authorization.
48. Professionally armoring a vehicle without authorization.
49. Homemade or improvised armoring of a vehicle without authorization.

Using the regulated vehicle carries five to fifteen years. Manufacturing, assembling, or armoring one without authorization carries four to ten years.

Article 84: Illegal introduction and trade of exclusive-use weapons

Article 84 is a major trafficking and illegal-entry statute, with a prison range of seven to thirty years.

The conduct includes:

50. Participating in illegally bringing automatic-fire conversion devices into Mexico.
51. Participating in bringing exclusive-use firearms into Mexico.
52. Participating in bringing firearm parts or components into Mexico.
53. Participating in bringing magazines into Mexico.
54. Participating in bringing ammunition or cartridges into Mexico.
55. Participating in bringing regulated explosives or controlled materials into Mexico.
56. A public official failing to prevent that introduction despite having a legal duty to do so.
57. Selling the items covered by the article.
58. Acquiring those items.
59. Commercializing those items.
60. Participating in their illegal trade.

The statute is not limited to the driver who physically crosses the border. The phrase “participates in the introduction” can potentially encompass other alleged participants, depending on their knowledge and contribution.

Article 84 Bis: Bringing nonexclusive firearms or regulated materials into Mexico

Article 84 Bis applies when the objects are not classified as reserved exclusively for the Armed Forces but are still introduced without the required permits.

The conduct includes:

61. Personally bringing a nonexclusive firearm into Mexico without authorization.
62. Participating in bringing that firearm into Mexico.
63. Bringing or helping bring firearm parts or components.
64. Bringing or helping bring magazines.
65. Bringing or helping bring ammunition or cartridges.
66. Bringing or helping bring fireworks, explosives, or related chemical substances.

The punishment is six to twelve years in prison, plus a fine.

This is particularly important for Americans who assume that a smaller-caliber or otherwise civilian firearm cannot result in a serious federal sentence. Even a weapon that is not reserved for military use may produce a major illegal-entry charge.

Article 84 Ter: Increased sentences for police, military, and security personnel

Article 84 Ter is not a separate offense. It is a sentence enhancement.

The punishment for specified offenses may be increased by as much as one-half when the accused is or was:

• A police officer.
• A member of a private security service.
• A member of Mexico’s Armed Forces.

The enhancement applies to the offenses specifically listed in the article.

Article 85: Unauthorized commerce, sale, or acquisition

Article 85 punishes three distinguishable forms of conduct:

67. Commercializing firearms, parts, components, or regulated materials without satisfying the law.
68. Selling or otherwise transferring those objects.
69. Acquiring those objects without proving their legal origin.

The sentence is six to ten years in prison, plus a fine.

The third category is especially noteworthy because it focuses on the buyer or recipient’s ability to establish lawful provenance.

Article 85 Bis: Illegal manufacture, export, assembly, and official-weapon diversion

Article 85 Bis carries seven to fifteen years.

The conduct includes:

70. Illegally manufacturing firearms.
71. Illegally manufacturing ammunition.
72. Illegally manufacturing firearm parts, components, magazines, cartridges, fireworks, or explosives.
73. Illegally exporting any of those objects.
74. A firearms dealer transferring ownership without the required permit.
75. Improperly disposing of firearms assigned to police agencies.
76. Improperly disposing of firearms assigned to prosecution or investigative agencies.
77. Improperly disposing of firearms assigned to the Armed Forces.
78. Manufacturing firearms from original parts or accessories.
79. Manufacturing firearms from improvised or homemade parts.
80. Manufacturing firearms from three-dimensionally machined or printed parts.
81. Assembling firearms from those parts or components.
82. Manufacturing devices that convert semiautomatic firearms into automatic firearms.

This provision reaches both traditional manufacturing and newer methods involving homemade, improvised, additive, or three-dimensional technology.

Article 85 Ter: Negligently causing the theft or loss of institutional firearms

Article 85 Ter punishes:

83. Negligently causing the theft of firearms covered by an institutional license.
84. Negligently causing the loss of those firearms.

It applies to weapons assigned to or acquired by police departments, prosecution agencies, local government institutions, and private security companies.

The sentence is one to three years. Repeat negligent conduct by private security personnel may lead to suspension or cancellation of the applicable license.

Article 86: Buying, transporting, repairing, transforming, or storing regulated objects

Article 86 punishes several actions committed without the appropriate permit:

85. Buying explosives.
86. Transporting objects regulated by the law.
87. Organizing or arranging regulated objects, using the broad wording appearing in the statute.
88. Repairing regulated objects.
89. Transforming regulated objects.
90. Storing regulated objects.

The basic penalty is four to six years. Transportation involving specified weapons, parts, components, magazines, ammunition, or cartridges may significantly increase the sentence. For some Article 11 categories, transportation may carry five to thirty years.

Article 86 Bis: Shipping firearms or explosives through postal or courier services

Article 86 Bis punishes:

91. Participating in sending firearms through the Mexican Postal Service.
92. Participating in sending firearms through a commercial courier or package-delivery company.
93. Shipping firearm parts or components through those services.
94. Shipping magazines, ammunition, or cartridges.
95. Shipping fireworks, explosive materials, or related chemical substances.

The ordinary range is three to five years. The prison sentence doubles when the shipment involves weapons, magazines, ammunition, or cartridges in specified Article 11 categories.

A person should not assume that mailing a component is legally safer than personally carrying it across the border.

Article 87: Permit-holder safety violations and unauthorized transportation companies

Article 87 covers regulated commercial and transportation activity.

The conduct includes:

96. Conducting a regulated activity under a general permit while failing to comply with mandatory safety conditions.
97. Sending firearms or regulated materials through a transportation company lacking the necessary federal permits.
98. Operating the unauthorized transportation service.
99. Selling explosives to a business or person without the required authorization.
100. Selling fireworks or related chemical substances contrary to the applicable permit and quantity rules.

The penalty is one month to two years, plus a fine.

Article 87 Bis: Improvised explosive devices

Article 87 Bis creates seven clearly distinguishable offenses involving an improvised explosive device:

101. Manufacturing an improvised explosive device.
102. Transporting an improvised explosive device.
103. Possessing an improvised explosive device.
104. Carrying an improvised explosive device.
105. Commercializing an improvised explosive device.
106. Transferring possession of an improvised explosive device.
107. Using an improvised explosive device.

The penalty is fifteen to thirty years. It may be increased by up to two-thirds when the device is intended for or used in organized-crime activities.

Article 87 Ter: Altering serial numbers and identifying data

Article 87 Ter punishes interference with the information used to identify and trace a firearm.

The separate conduct includes:

108. Illicitly marking firearm-identification data.
109. Modifying a serial number, registration number, unique weapon number, manufacturer information, or place-of-manufacture data.
110. Destroying or removing identifying or tracing information.

The penalty is three to six years, plus a fine.

Article 87 Quáter: Up to seven firearm parts or components

Article 87 Quáter applies to quantities of up to seven firearm parts or components.

It separately punishes:

111. Possessing up to seven firearm parts or components.
112. Carrying up to seven parts or components.
113. Trading or commercializing up to seven parts or components.
114. Transporting up to seven parts or components.
115. Illegally bringing up to seven parts or components into Mexico.

The penalty depends on the classification of the firearm for which the parts were designed:

• Article 9 firearms: three to five years.
• Article 11(a) or 11(b) weapons: four to six years.
• Other Article 11 weapons: five to ten years.

The statute identifies barrels, frames or receivers, bolts, cylinders, locking mechanisms, and devices intended to reduce the sound of a gunshot as examples of regulated parts or components.

Article 87 Quinquies: Stockpiling more than seven firearm components

When more than seven parts or components are involved, Article 87 Quinquies applies.

The conduct includes:

116. Stockpiling more than seven firearm parts or components.
117. Possessing more than seven parts or components.
118. Carrying more than seven parts or components.

The statute defines stockpiling for this purpose as possession or carrying of more than seven pieces or components.

The prison range is:

• Four to six years for parts associated with Article 9 firearms.
• Six to eight years for Article 11(a) or 11(b) weapons.
• Six to twelve years for parts associated with the other Article 11 weapons.

Articles 88 and 89: Confiscation and license consequences

Articles 88 and 89 generally do not create separate criminal acts.

Article 88 regulates confiscation, custody, destruction, or disposition of firearms, ammunition, accessories, explosive devices, and armored vehicles connected to the offenses in this chapter.

Article 89 permits Mexico’s Defense Ministry to suspend or cancel licenses or permits in addition to any criminal punishment.

Article 89 Bis: Private security companies using firearms after license cancellation

Article 89 Bis applies to owners or administrators of private security companies that violate Article 30 Bis.

The prohibited failures may involve:

119. Allowing the company to use firearms after its collective private license has been canceled.
120. Failing to deliver those firearms to the designated military facility for safekeeping within fifteen business days.
121. Failing to dispose of the firearms through the authorized procedure within forty-five business days after they enter Defense Ministry custody.

The penalty is two to five years, plus a fine. Whether each omission is charged independently will depend on the prosecutorial theory and the facts of the case.

Can these offenses lead to mandatory pretrial detention?

Yes, some can.

Article 92 identifies specific offenses and firearm categories that qualify for Mexico’s constitutionally regulated form of automatic or mandatory pretrial detention, known as prisión preventiva oficiosa. The list includes significant portions of Articles 83, 83 Bis, 83 Ter, 83 Quáter, 83 Sexies, 83 Septies, 84, 85 Bis, 86, 87 Bis, 87 Quáter, and 87 Quinquies when the statutory conditions are met.

That does not mean every person arrested with any firearm must automatically remain in prison. The prosecution must still establish the legally relevant classification, quantity, conduct, and connection to the particular statutory provision.

Common scenarios involving Americans at the Mexican border

Many cases involving U.S. travelers do not begin with an allegation that the person intended to traffic weapons. They begin with ordinary travel circumstances:

• A handgun left inside a center console.
• A range bag forgotten in an SUV.
• Loose ammunition under a seat.
• A magazine inside a backpack.
• A firearm stored in an RV or toy hauler.
• A wrong turn that prevents the driver from returning to the United States.
• A driver who does not understand instructions given in Spanish.
• A vehicle shared with another person.
• A gun part ordered online and shipped to Mexico.
• A firearm owned by a passenger rather than the driver.

These facts do not automatically erase criminal exposure, but they may be central to issues such as knowledge, possession, control, intent, voluntariness of entry, reliability of the police report, legality of the search, access to an interpreter, and the correct legal classification.

What should an American do after a firearm arrest in Mexico?

Do not sign a statement that you do not fully understand. Request a qualified interpreter. Clearly state that you want legal counsel. Avoid guessing about the firearm, its ownership, or how it entered the vehicle. Do not agree with an officer’s version merely because you are frightened or confused.

The first hours matter. Defense counsel should obtain and examine the arrest report, customs records, photographs, body-camera or surveillance material when available, firearm examination, ammunition count, vehicle location, witness statements, border-lane evidence, and any communications showing the traveler’s original destination.

A gun case in Mexico can move quickly, and what happens during the initial detention may shape the entire prosecution.

Final takeaway for U.S. travelers

Do not assume that American gun rights travel with you across the border.

Before entering Mexico, inspect your vehicle carefully. Check the glove box, center console, door compartments, under the seats, trunk, luggage, backpacks, range bags, trailers, and RV storage areas. Look not only for firearms, but also for ammunition, magazines, suppressor-type devices, conversion devices, frames, receivers, barrels, bolts, and other components.

A quick inspection before leaving California can prevent years of criminal litigation in Mexico.

If an arrest has already occurred, the case should be evaluated under the exact language of the Mexican statute—not assumptions based on California or U.S. firearms law.

Final Thoughts: Mexico’s Constitution Requires the Strictest Treatment of Illegal Weapons Cases

For U.S. citizens—especially travelers entering Mexico from California—this is not merely another technical firearms regulation. Article 19 of the Mexican Constitution establishes an exceptionally severe constitutional policy toward the illegal manufacture, distribution, transfer, transportation, or introduction of weapons into Mexican territory.

The language is direct. It applies to both Mexican nationals and foreign citizens involved in these activities and requires the imposition of the most severe legally available punishment, as well as prisión preventiva oficiosa, commonly understood as mandatory pretrial detention, when the constitutional and statutory requirements are met. The provision also instructs Mexican authorities to apply its wording literally and prohibits interpretations intended to suspend, weaken, modify, or render it ineffective.

In practical terms, this means that judges are constitutionally directed to treat these cases with extraordinary seriousness. A person accused of illegally bringing weapons into Mexico may face incarceration while the case is pending, even before there has been a conviction. The fact that the firearm was lawfully purchased, registered, or carried in California does not automatically provide legal authorization in Mexico.

However, the Constitution’s command of literal interpretation also creates an important legal safeguard. Prosecutors and judges cannot expand the provision through analogy simply because a case involves a firearm. The government must establish that the accused person’s conduct falls within one of the actions expressly identified by the Constitution and the applicable federal statute, such as manufacturing, distributing, transferring, transporting, or illegally bringing weapons into Mexico. The prosecution must still prove every legally required element, and the accused continues to have the right to challenge possession, knowledge, intent, firearm classification, the legality of the search, the accuracy of the arrest report, and the voluntariness of the border crossing.

The takeaway could not be clearer: Mexico does not treat an illegal weapons case as a minor travel mistake. It treats it as a matter of national security and sovereignty. For an American traveler, one forgotten handgun, magazine, box of ammunition, firearm component, or wrong turn at the border can lead to federal prosecution and pretrial incarceration.

That is why immediate representation by a Mexican criminal defense attorney familiar with federal firearms law, border procedures, and the rights of foreign defendants is not simply helpful—it can be critical to protecting the accused person’s freedom and building an effective defense from the very first hours of the case.