Coggins Test

To prevent the spread of equine infectious anemia (EIA), all stock (horses, burros or mules) within Yellowstone National Park must have a negative EIA or Coggins test within the last 12 months. If you are anywhere in Yellowstone National Park, whether on a day ride or an overnight horse trip, your stock must be tested and you must carry proof of a negative Coggins test for each animal. Photocopies of Coggins tests are acceptable in the backcountry. This regulation applies even if you are:

  • Not crossing state lines
  • Not passing through an entrance station
  • Just driving through and not stopping
  • Entering the park from a backcountry trailhead

If you are planning to stay overnight in the backcountry, you must obtain a backcountry permit.

You can obtain a permit at any backcountry office or contact the Central Backcountry Office at 307-344-2160.

For more information or questions on horseback riding in the park contact the Central Backcountry Office at 307-344-2160.

Please make sure that the date blood drawn (within 12 months of current date), the laboratory name & negative test results, and identifying features of each animals (name, brand, identifying markings or scars) and are legible on your Coggins forms.

Sample Coggins Test Form

Last updated: June 9, 2017

Contact the Park

Mailing Address:

PO Box 168
Yellowstone National Park, WY 82190-0168



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