The 1908 West Down by-election was held on 20 March 1908. The by-election was held due to the resignation of the incumbent Irish Unionist MP, Arthur Hill. It was won by the Irish Unionist candidate William MacCaw.
|Irish Unionist||William MacCaw||4,051||59.5||N/A|
|Ind U||Andrew Beattie||2,760||40.5||N/A|
|Irish Unionist hold||Swing||N/A|