From 1 January 2012 all pet dogs, cats and ferrets entering the UK under the Pet Travel Scheme must be identified. This will usually be by microchip.

There is one exception for pets that have been identified by a tattoo which was applied on or before 3 July 2011. If the tattoo is clearly legible, and the tattoo was applied before the pet was vaccinated against rabies, then the pet does not need to be microchipped. The date of tattooing, the tattoo number and vaccination must be recorded in the pet passport or official third country veterinary health certificate.

If a pet cannot be readily identified by a tattoo before it enters the UK under the Pet Travel Scheme, it may be refused entry. It can be licensed into quarantine and released early once it has met all of the requirements of the Scheme.