Cattle Identification

​Note: Federal rule changes go into effect November 5, 2024, that require official ear tags applied to cattle and bison to be readable both visually AND electronically. This requirement applies to official identification placed for any reason, including interstate movement, brucellosis vaccination, and tuberculosis testing. Cattle tagged with visual-only official tags prior to November 5, 2024, do not need to be retagged unless they lose their ID and are being moved, tested, or vaccinated under circumstances that require official ID. These changes only affect cattle and bison – other species are not affected.

The only change regarding which cattle and bison require official ID in Wisconsin is the addition of official ID required for dairy/beef crosses moving interstate.


Summary of Wisconsin Cattle Official ID Requirements 

Within-State ("Intrastate") Requirements

  • Cattle and bison vaccinated against brucellosis require official ID. When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used. 
    • Although orange 840 RFID tags are available to veterinarians for brucellosis vaccination, any 840 RFID tag can be applied at the time of vaccination and recorded. Until November 5, 2024, orange metal tags can be applied as official ID at the time of vaccination.
    • If a calf already has an 840 RFID tag at the time of vaccination, another 840 RFID tag should not be applied. Until November 5, 2024, in these cases an orange metal tag can be, but is not required to be, applied. Effective November 5, 2024, in these cases no new tag should be applied, and the existing tag number should be recorded. 
  • Cattle and bison tested for diseases such as tuberculosis, influenza, brucellosis, and Johne's disease require official ID. When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used.
  • Wisconsin cattle and bison staying on farms or moving INTRAstate to other farms or to fairs, recreational events, shows, or exhibitions do not require official ID.
    • Fairs, recreational events, shows, or exhibitions may choose to require ID for cattle and bison, including official ID. Check with the event.
  • Markets and dealers have requirements to identify cattle and bison under ATCP 12.05. The federal rule change does not affect or change when cattle are required to be officially identified under 12.05 for intrastate movement.
    • When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used.
    • ATCP 12.05 requires markets and dealers to officially identify cattle and bison: steers, calves under 6 months old, feeder cattle, and cattle and bison backtagged for slaughter remain exempt from official identification requirements for intrastate movements.
    • Feeder cattle include steers and beef heifers not more than 18 months of age kept solely for feeding prior to slaughter. For intrastate movements only, state rules continue to classify beef and dairy crossbreds as beef animals.
    • Markets and dealers may choose to officially identify cattle and bison exempted under ATCP 12.05.

Interstate Movements

  • All cattle moving across state lines to attend rodeos, recreational events, shows, and exhibitions, including all beef cattle and steers, require official ID. When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used.
  • For exports out of Wisconsin to farms, check with the state of destination for ID requirements. At a minimum, federal rules require official ID for sexually intact beef cattle 18 months of age and over and all dairy cattle. When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used.
  • For imports to Wisconsin farms, all cattle, except beef steers, require official ID. When official ID is applied, effective November 5, 2024, 840 RFID tags will need to be used.
  • The federal rule clarifies the definition of dairy cattle to include crossbred calves of any breed that are born to dairy cattle. This means effective November 5, 2024, these dairy/beef crossbreds will need to be identified as dairy cattle for interstate movement.
  • Cattle and bison may continue to move interstate directly to a slaughtering establishment with a backtag.
  • Cattle and bison may continue to move interstate to no more than one federally approved market without official ID. From a Wisconsin federally approved market the cattle or bison must then move directly to a slaughtering establishment on a backtag or have official ID applied and a certificate of veterinary inspection (CVI) written as required for the interstate movement.

Official ID for Cattle and Bison:

  • 840 RFID tags: These are radio frequency identification (RFID) tags that have a 15-digit number, the first three of which are 840. These tags have the U.S. shield.
  • 124 RFID tags: These are 15-digit tags with the first three digits of 124 and are official tags for animals originating in Canada. These are recognized as official ID and should not be removed or replaced. 
  • 840 Visual-only tags if applied prior to November 5, 2024: These tags have a 15-digit number, the first three of which are 840, and do not have an electronic/RFID component. These tags have the U.S. shield.
    • Effective November 5, 2024, visual-only 840 tags cannot be applied to cattle for use as official ID. Cattle tagged with visual-only 840 tags prior to November 5, 2024, are officially identified for their lifetimes and do not need to be retagged unless they lose the visual-only 840 tag and require official ID.
  • National Uniform Ear-tagging System (NUES) ear tags if applied prior to November 5, 2024: These are usually silver or orange metal clip tags that have the format 35 (state 2-digit code) ABC 1234. Plastic NUES tags are also available. 
    • Effective November 5, 2024, NUES tags cannot be applied to cattle for use as official ID. Cattle tagged with NUES tags prior to this date are officially identified for their lifetimes and do not need to be retagged unless they lose the NUES tag and require official ID.
  • American ID if applied prior to March 11, 2015: These are visual tags that have USA followed by an 8- to 12-digit number. If tagged with these tags prior to March 11, 2015, cattle are considered officially identified and the tag does not need to be replaced.
  • Manufacturer-coded RFID tags if applied prior to March 11, 2015: These are RFID tags that contain a 15- digit number starting with the manufacturer's 3-digit code in the 900 series. If tagged with these tags prior to March 11, 2015, cattle are considered officially identified and the tag does not need to be replaced.