A person is qualified if they are a Commonwealth citizen (which includes a British subject) or a citizen of a member state of the European Union, is over 18, and is an elector. In addition, they will be qualified if they have either during the whole of the twelve months before the day on which they are nominated as a candidate, or the day of the election, resided in the locality or within three miles of it or occupied as owner or tenant any land or premises therein or had their principle or only place of work there. Such work need not be paid, but must be substantial; it may even include duties which the candidate was elected to perform before the election by the very same council as that to which they are now seeking election. One effect of these rules is that it is possible to be a member of more than one council.

Local Government Association 1972, s 70
Parker vs Leo (1992) 90 LGR (court of Appeal)

Source: Paul Clayden: Arnold-Baker on Local Council Administration