Yes they do. This is a legal requirement. Dogs must wear a collar in public. To avoid a hefty fine, owners must also make sure that the dog displays their name and address.
By law, dogs in a public place, it must wear a collar. This collar, a tag attached to the collar, must also bear its owner’s name and address.
Be aware that owners can be fined up to £2000 if they don’t comply. (There are a few exceptions, look at this link: http://www.legislation.gov.uk/uksi/1992/901/article/2/made).
Although it’s not law for the collar or tag to also display the owner’s postcode and phone number, some feel this is advisable, in order to aid a pet’s quick return if he or she is lost.
Many owners believe that if their dog is microchipped, they do not need to have a named collar or tag – this is incorrect. Visual identification is still required (and is also needed in addition to the tag a dog return company might provide). In addition to the legally required identification we recommend microchipping. It makes it easier to identify and return stolen dogs whose collars, or tags, may have been removed. Be aware microchipping is likely to become mandatory in 2016.