Seaham was a parliamentary constituency, in existence between 1918 and 1950, of the House of Commons of the Parliament of the United Kingdom. It elected one Member of Parliament (MP) by the first past the post system of election.

South East Durham was a county constituency represented in the House of Commons of the Parliament of the United Kingdom. It elected one Member of Parliament (MP) by the first past the post system of election between 1885 and 1918.