If you keep cattle, bison or buffalo in England or Wales, every calf born on your holding must be identified with official ear tags, entered in your holding register and registered with the British Cattle Movement Service (BCMS). Registering the birth is how you get the passport that records the animal's movements from birth to death. The rules apply however few animals you keep.
Fit two official ear tags
Buy official ear tags from an approved supplier. The supplier registers the tags against your county parish holding (CPH) number and herd mark, so order only the number you expect to use in a year.
Bison calves follow a different rule: fit both tags when the calf is separated from its dam or before it is 9 months old, whichever is sooner.
Register the birth and get a passport
Replace lost or damaged tags
If an animal you buy arrives with a tag missing, order a replacement from an approved supplier and do not move the animal off your holding until it is fitted.
Electronic tags for calves in England from 2027
On 2 June 2025 Defra announced that electronic identification will be mandatory for all newborn calves in England from 2027, using low frequency ear tags that can be scanned when animals move. Keep fitting the tags described above until electronic tags become mandatory.
Legal basis
Primary legislation and key regulations
Browse UK legislation (opens in a new tab) legislation.gov.uk