Livestock Microchipping Laws in Arizona: What Producers Need to Know

If you raise cattle, horses, sheep, goats, or swine in Arizona, the rules around official animal identification have changed significantly in recent years — and microchips sit at the center of the debate. The federal government now requires electronic identification for certain cattle and bison crossing state lines, while Arizona’s own traceability system layers additional requirements on top of that baseline.

Understanding exactly where a microchip fits — and where it does not — can save you from compliance problems at auction, during interstate transport, or when a disease investigation requires rapid traceback. This guide breaks down the current rules, species by species, so you know what Arizona and federal law actually require of you.

Pro Tip: Before implanting any microchip for official identification purposes, confirm your Premises Identification Number (PIN) is active with the Arizona Department of Agriculture. Orders for USDA 840 official microchips cannot ship until your Flock and/or Premises IDs are verified.

Microchipping vs. RFID Ear Tags: What Counts as Official ID in Arizona

The terms “microchip” and “RFID ear tag” are often used interchangeably in casual conversation, but they are distinct technologies under state and federal identification rules. RFID ear tags are a type of identification tag attached to the ear of livestock, and the “RFID” refers to the technology that transmits and receives data via radio waves — each tag contains a small electronic chip with a unique animal identification number. An implantable microchip, by contrast, is injected under the skin or into muscle tissue and read with a handheld scanner.

Radio frequency identification (RFID) microchips are implanted in animals, making them a subcutaneous form of electronic ID rather than an external ear tag. Both technologies can carry a USDA Animal Identification Number (AIN), but they are treated differently depending on species and the movement context involved.

In Arizona, “livestock” includes cattle, equine (horses, mules, burros, asses), sheep, goats, and swine, except feral pigs. For most of these species, official identification can take the form of an ear tag, tattoo, brand, or microchip — but only when the specific device meets USDA approval standards. Arizona’s Seasonal Pass application for single livestock animals lists permanent ID options as ear tag, brand, tattoo, microchip, or ear notch, and notes this is required for sheep, goats, swine, and most out-of-state cattle.

Ear tags are effective and visible means of identification, but can be removed intentionally or by trauma. An implanted microchip, once placed, cannot be removed without a veterinary procedure — which gives it a permanence advantage that Arizona courts and livestock inspectors recognize when evaluating proof of ownership disputes.

The Federal RFID Mandate and What It Means for Arizona Producers

The animal disease traceability regulations were set forth in a final rule published on January 9, 2013, contained in 9 CFR part 86, and provide the requirements for identification and documentation for certain classes of cattle and bison to move interstate, establishing minimum national official identification and documentation requirements for the traceability of livestock moving interstate.

That 2013 rule allowed producers to choose between electronic and traditional forms of ID. That changed in April 2024. USDA’s Animal and Plant Health Inspection Service (APHIS) announced a final rule mandating electronic identification (EID) tags for interstate movement of certain cattle and bison, stating that 180 days after publication, all official ear tags applied to such cattle and bison must be visually and electronically readable. The regulation enhances the previous 2013 rule that requires all sexually intact cattle and bison 18 months of age or older, dairy cattle, and rodeo and exhibition cattle to have an official form of animal identification.

This rule became effective November 5, 2024. For Arizona producers, that means any covered cattle or bison receiving a new official ear tag on or after that date must carry a tag that is both visually and electronically readable — a plain metal or plastic visual-only tag no longer qualifies for new applications.

If a cow has already been tagged with a visual-only official identification tag prior to the rule’s effective date, producers are not required to apply an electronically readable tag to the animal. So existing visual tags on older animals remain valid for the life of those animals.

Important Note: The November 2024 EID mandate applies specifically to cattle and bison ear tags for interstate movement. It does not directly mandate implantable microchips for cattle — but it does make RFID the required technology in any official ear tag applied after the effective date. Microchips remain a separate, approved identification method for equine and small ruminants under different provisions.

Arizona’s traceability road map aims to enhance the ability to track animals from birth to slaughter through a system that allows tracking data points to be connected, and to elevate the discussion with states and industry to work toward a system where animal health certificates are electronically transmitted from private veterinarians to state animal health officials. The Arizona Department of Agriculture (AZDA) has implemented electronic Certificate of Veterinary Inspection (eCVI) capability through USAHERDS to support that goal. You can review Arizona’s full traceability framework on the USDA APHIS Arizona ADT Road Map.

Which Livestock Can Use a Microchip as Official Identification in Arizona

Not every species in Arizona can use an implantable microchip as its primary official identification. The rules vary by species, and understanding those differences keeps you on the right side of both state and federal requirements. If you raise backyard pigs or other small livestock, our guide to backyard pig laws in Arizona covers additional permitting context you should review alongside these ID rules.

Equine (Horses, Mules, Burros, Asses): The USDA 840-ID Official Microchip can be used in all equines, goats, sheep, alpaca, llama, elk, whitetail and other deer, and more. For horses specifically, an ISO-compliant microchip is a well-established and widely accepted form of official identification, particularly for interstate health certificates and breed registry documentation.

Sheep and Goats: National Premises IDs are for cattle, bison, swine, and are only used for sheep and goats in lieu of an Arizona Flock ID if purchasing microchips. Arizona Flock IDs are tied to animals. This means that if you choose a microchip as your official ID method for sheep or goats, you must obtain a National Premises ID rather than relying solely on the Arizona Flock ID system. Sheep and goats must be identified with your Arizona Flock ID number, by either a tattoo or a specially-made tamper-proof ear tag applied by you — unless you opt into the microchip pathway, which requires the premises ID route instead.

Swine: Producers and breeders are required to tag each individual swine with either a tamper-proof tag or tattoo them with their Arizona Flock ID number. A microchip can serve as supplemental or alternative permanent ID for swine, but the AZ Flock/Premise ID must still be associated with the animal.

Cattle and Bison: For cattle and bison moving interstate, the November 2024 rule now requires that new official ear tags be RFID-enabled. Implantable microchips are not the standard identification method for cattle under the federal ADT rule, though they can supplement herd records. Brand inspection of all cattle is a requirement of shipments when transferring ownership or to slaughter, and multiple accredited veterinarians in Arizona have had the orange 840 tags issued to them for the purposes of identifying official calfhood vaccinates.

When a Microchip Qualifies for Interstate Movement in Arizona

Moving livestock across state lines triggers federal traceability requirements that sit on top of Arizona’s intrastate rules. Unless exempted, livestock belonging to species covered by the regulations that are moved interstate must be officially identified and be accompanied by an interstate certificate of veterinary inspection or other movement document. The rule covers cattle and bison, horses and other equine species, poultry, sheep and goats, swine, and captive cervids.

For equine, a microchip encoded with a USDA 840 Animal Identification Number is a recognized form of official ID for interstate movement when recorded on the Interstate Certificate of Veterinary Inspection (ICVI). In 2015, the USDA approved 840 microchips for encoding with USDA 840 ID Numbers, meaning they can be used for official USDA identification to comply with USDA and APHIS regulations. Your accredited veterinarian records the microchip number on the health certificate, and that document travels with the animal.

For cattle and bison, the microchip is generally not the primary interstate identification device under the current ADT rule. The pending requirement narrows in on sexually intact cattle and bison that are 18 months of age or older, all dairy cattle, and any cattle or bison used for rodeo or recreation events. Those animals need an RFID ear tag — not just a microchip — to move interstate legally after November 5, 2024.

For sheep and goats traveling interstate, animals requiring an entry permit — swine, cattle, sheep, and goats — can be traced to an associated Certificate of Veterinary Inspection (CVI) in real time. If you use a microchip as the official ID for small ruminants, that chip number must appear on the CVI. Our article on transporting livestock laws in Arizona covers the broader documentation requirements for any interstate or intrastate livestock movement.

Pro Tip: Arizona maintains a mandatory record retention schedule of between five and seven years to comply with ADT requirements and state law. Keep copies of all CVIs, microchip implantation records, and premises registration documents for at least that long.

Approved Microchip Standards and Placement by Species in Arizona

Not every microchip qualifies as official identification. USDA APHIS maintains a list of approved Animal Identification Number (AIN) devices, and only chips from approved manufacturers carrying the 840 prefix are accepted as official ID. One of the permitted methods of identification is a 15-digit microchip that begins with the designated United States prefix 8-4-0 (for example, 840123456789012). Only USDA-approved companies are granted permission to manufacture the official 840 microchip.

The frequency standard matters too. Approved devices for EIDs include 134.2 kHz LF RFID tags compliant with both the 11784 and 11785 ISO standards, or UHF RFID tags. For implantable microchips specifically, the ISO 11784/11785 standard at 134.2 kHz is the accepted frequency for livestock identification in the United States. The American National Standards Institute (ANSI) voted in favor of the current International Standards Organization (ISO) standards both at the time of initial adoption in 1996 and at the time of their mandatory five-year reviews in 2001 and 2006.

Placement guidelines by species follow veterinary best practices and USDA recommendations:

• Horses and equine: The standard implant site is the left side of the neck, in the nuchal ligament, approximately midway between the poll and withers. This placement is recognized internationally and aligns with breed registry requirements.
• Sheep and goats: Microchips are typically implanted in the ear base or the tail fold, depending on the manufacturer’s guidance and the veterinarian’s preference. USDA-approved injectable transponders for sheep and goat identification are available as FDX-format AIN devices.
• Swine: Implantation in the ear or neck area is standard, though tamper-proof ear tags or tattoos remain the more common identification method for swine in Arizona.
• Deer, elk, alpaca, and llama: The 840-ID Official Microchip can be used in zoo animals requiring an ICVI or for other reasons, in addition to equines, goats, sheep, alpaca, llama, elk, and whitetail and other deer.

The AVMA recommends that microchip implantation be performed by a licensed veterinarian or under veterinary supervision. If you are implanting chips in animals you plan to move interstate, having a licensed vet perform the procedure also ensures the chip number is properly documented on health certificates. For context on how Arizona regulates animals more broadly, see our overview of goat ownership laws in Arizona.

Registering a Livestock Microchip in Arizona

Implanting a chip is only half the process. For the microchip to function as official identification, the Animal Identification Number it carries must be tied to a registered premises and, for certain species, a Flock ID. A premises identification number (PIN) or location identifier (LID) is a unique code permanently assigned to a physical location and is required to purchase official animal identification tags. Each state administers PIN or LID registration.

In Arizona, the Arizona Department of Agriculture handles premises registration through the Office of the State Veterinarian. The process differs slightly by species:

• Cattle, bison, swine: Obtain a National Premises ID from AZDA. This number links your physical location to any official identification devices — including microchips — associated with animals on that property.
• Sheep and goats (microchip pathway): You must have both a Premises ID Number and a Flock (Scrapie) ID Number. To get your Premises ID, visit your state-specific Animal Health Office or call your state veterinarian’s office. To get your Scrapie Flock ID, call 866-873-2824.
• Horses, alpaca, llama, deer, and elk: You must have a Premises ID Number. No separate flock or herd ID is required for these species.

If you move, your ID does not move with you, so you would need to reapply for a new Premises ID number. This is an easy detail to overlook when relocating a livestock operation across county lines or to a new property. Note that 840 microchip orders cannot ship until Flock and/or Premises IDs are verified, so complete your registration before ordering chips.

Arizona has a state mandatory record retention schedule of between five and seven years to be compliant with ADT requirements and satisfy state law. Keep your premises registration confirmation, chip implantation records, and any associated CVIs in a secure file for at least that period. The AZDA Animal Services Division, Office of the State Veterinarian, is responsible for implementing the animal disease traceability system for the state of Arizona. You can reach the State Veterinarian’s office at 602-542-4293 for registration questions.

Microchipping as Proof of Ownership in Arizona

Beyond regulatory compliance, a microchip serves a practical ownership function that Arizona’s livestock inspection system recognizes. The Arizona Department of Agriculture protects the public from contagious and infectious disease in livestock, poultry, commercially raised fish, meat, milk, and eggs by enforcing laws concerning the movement, sale, importation, transport, slaughter, and theft of livestock. When livestock theft or a disputed ownership claim arises, a microchip tied to a registered premises and a recorded bill of sale provides strong, tamper-resistant evidence of ownership.

Unlike a brand — which can be altered — or an ear tag, which can be removed, an implanted chip is difficult to falsify. Beyond practical everyday use, microchip products have been used for prevention of livestock theft, natural disaster recovery of livestock, recovery of stolen animals, and breed registry databases. In a state like Arizona, where cattle rustling and range disputes remain real concerns for ranchers across Cochise, Graham, and Yavapai counties, a chip number recorded with your premises registration creates a paper trail that holds up in court.

A microchip alone, however, is not a substitute for Arizona’s livestock inspection and brand registration system. Inspections are required for ownership, control, and regulation of livestock by law and rule. When you sell, transfer, or transport livestock in Arizona, a livestock inspection certificate or self-inspection certificate is still required alongside any electronic identification. The microchip number should appear on that certificate to create a complete chain of documentation.

For producers who also keep companion animals on the same property, it is worth noting that Arizona’s microchipping rules for dogs and cats operate under an entirely separate legal framework. Our guides to dog leash laws in Arizona and pet custody laws in Arizona cover those companion animal rules in detail.

Key Insight: If you purchase livestock that arrives with an existing microchip, record that chip number on your bill of sale and notify your accredited veterinarian so it can appear on future health certificates. A chip registered to a previous premises in another state does not automatically transfer ownership records to you — you must document the transaction independently.

Staying current with both AZDA requirements and federal ADT rules is the most reliable way to protect your animals, your investment, and your ability to move livestock freely across state lines. When in doubt, contact the Arizona State Veterinarian’s office directly — or work with an accredited veterinarian who can confirm which identification method applies to your specific species, herd size, and intended movement. For related reading on how Arizona regulates other animals on your property, see our articles on beekeeping laws in Arizona and rooster laws in Arizona.