Beef Identification (EID / RFID)

Last updated: September 26, 2025

Electronic identification (EID, commonly called RFID) is the standard for official identification of cattle in Michigan and for certain classes of cattle and bison that move across state lines. This page summarizes what producers, youth exhibitors, veterinarians, and market operators need to know and do.

Why identification matters

• Fast, accurate traceability limits the number of animals and owners caught up in a disease investigation and shortens response time.

• In Michigan, official ID supports bovine tuberculosis (TB) surveillance and movement controls.

Michigan requirements (intrastate movement)

All cattle leaving a Michigan premises must bear official identification before they move, unless the first point of destination is a state‑approved tagging‑agreement site (for example, a livestock market that will apply official tags on arrival). Animals that pass through a Michigan market must leave with official ID applied.

What qualifies as “official ID” in Michigan? For cattle, official ID means an electronic radio frequency identification (EID/RFID) ear tag or other forms of official ID as approved by the state animal health authority. In practice, producers should use official 15‑digit “840” EID ear tags for cattle and bison.

Premises Identification Number (PIN) required to buy 840 tags. To purchase official 840 tags, you must have the PIN for the location where the animals are housed.

Learn more: MDARD – Bison & Cattle requirements · MDARD – Animal ID & Movement · Michigan statute: MCL 287.711b

Federal requirements (interstate movement)

Beginning November 5, 2024, official eartags applied on or after that date to cattle and bison that require individual official ID for interstate movement must be both visually and electronically readable (EID). This federal rule does not change which classes of cattle/bison require official ID to cross state lines. Covered classes include:

  • Sexually intact cattle and bison 18 months of age and older

  • All dairy cattle (female dairy cattle of any age and male dairy cattle born after March 11, 2013)

  • Cattle and bison of any age used for rodeo/recreation, shows, and exhibitions

Exemptions. Animals moving direct to slaughter (or through an approved market to slaughter) are exempt from official ID. Beef feeder cattle under 18 months of age are not required to have official ID unless otherwise required by a disease program or by a receiving state.

Previously tagged animals. Non‑EID official eartags applied before Nov. 5, 2024 remain valid. If you apply a new EID tag to an already officially identified animal, you must record both tag numbers and the date the new tag was applied (see “Recordkeeping & paperwork”).

Learn more: Federal Register final rule · APHIS announcement · ADT overview · Interstate movement decision tree (PDF)

Tag types & standards (what to buy)

  • AIN “840” tags indicate U.S. origin and are the standard official ID for cattle and bison.

  • EID technologies: Both HDX (half‑duplex) and FDX (full‑duplex) low‑frequency ear tags meet U.S. standards for official EID. Either is acceptable for official purposes. Choose based on your reader equipment and management software.

  • Printed elements: Official tags display the 15‑digit AIN (starts with 840), the official ear tag shield, and “Unlawful to Remove.”

  • Which ear? Left ear is recommended, but either ear is acceptable. Apply in the middle third of the ear between the cartilage ribs.

Getting a PIN and buying tags

  1. Get or confirm your Premises Identification Number (PIN). The PIN is required to purchase 840 tags. In Michigan, call MDARD Atlanta Field Office: 888‑565‑8626 (listed under Animal ID). See: MDARD Animal ID & Movement and USDA’s overview: How to obtain a PIN.

  2. Buy 840 EID tags from approved vendors (local or online). Michigan provides:

Tip: Use the correct tagger for the brand/model you buy, and match HDX/FDX tag choice to any existing reader/software at your farm or market.

Tagging best practices

  • When to tag: Apply the official tag well before movement (e.g., at processing, preconditioning, or prior to sale/shipment) to avoid delays.

  • Placement: Middle third of the ear, between the two cartilage ribs; avoid blood vessels. Follow brand‑specific instructions.

  • Hygiene & retention: Clean applicator and ear. Ensure firm closure; check retention before animals leave the chute.

  • Avoid duplicates: Check for an existing official tag before applying a new one. If re‑tagging is necessary, retain records linking old and new official numbers.

Recordkeeping & paperwork

  • Tag distribution records: Entities that distribute official ID devices (states, tribes, veterinarians, tag vendors/markets) must keep distribution records for 5 years.

  • Re‑tagging records: If you apply an EID tag to an animal that already had an official (non‑EID) tag, record both official numbers and the application date and keep the record for 5 years.

  • Movement documents: Most interstate movements require an ICVI (health certificate) or other approved documentation agreed upon by both states (e.g., brand inspection certificate in brand states). The animal’s official ID number(s) must be recorded unless an exception applies.

Practical tip: Even when not strictly required, keeping a simple list that ties each animal’s official ID to its visual management tag, sex, class, and shipment (date/destination) pays off during a traceback.

Readers & data systems

  • Readers are not required by federal rule, but they can speed up processing, reduce transcription errors, and connect on‑farm management data to movement records.

  • Most commercial systems read both HDX and FDX low‑frequency tags; confirm compatibility before purchasing.

Who to contact

Disclaimer

This page summarizes requirements current at the time of publication. Always confirm the latest import, exhibition, and interstate movement rules for your destination. Receiving states and exhibition organizers may impose additional requirements.

Fact Sheets