Any person who is a British or Commonwealth citizen or citizen of the Republic of Ireland, over 18 years of age and not otherwise disqualified from office may stand as a candidate.  People who hold certain offices may be disqualified from being a candidate and these are detailed in the House of Commons Disqualification Act 1975 as follows:-

Judges, civil servants, members of HM forces, police officers and many government appointees.

The House of Commons Clergy Disqualification Act 1801 prevented some clergy from becoming MPs but the House of Commons Removal of Clergy Disqualification Act 2001 has now removed that disqualification from most clergy.

Holders of hereditary peerages who are permitted to sit in the House of Lords are disqualified from being elected to the Commons.

The Representation of the People Act 1981 prevents anyone who has been imprisoned or detained for more than 1 year from being elected to the House of Commons.