The Star Line was a fleet of ships owned by timber merchants, Messrs. James P Corry and Co Ltd. of Belfast, Ireland. The shipping company was formed by Robert Corry in 1826 to import timber from Canada to Ireland. The company began to diversify in 1859 when trade with Calcutta began and the company relocated its offices from Belfast to London. This was followed by services to Australia and New Zealand in 1888, South America in 1903 and a joint emigrant service to Australia with Royden and Tyser Lines started in 1912. The company became a constituent part of the Commonwealth & Dominion Line in 1914, which was renamed Port Line in 1937.

Port Line was a passenger and cargo shipping company, initially formed as the Commonwealth and Dominion Line in 1914, and in operation in one form or another until 1982.