HMS Halsham was one of 93 ships of the Ham class of inshore minesweepers of the Royal Navy.

The minesweeper was named after Halsham in the East Riding of Yorkshire.

By 1972, she was the only remaining RAF-operated marine asset, and to provide continued efficient management she was transferred to the Royal Corps of Transport's civilian fleet and renamed Richard George Masters (later shortened to R G Masters).

[1] Private Masters was the sole recipient of the Victoria Cross in the Royal Army Service Corps during the First World War.

This article about a specific naval minesweeper of the United Kingdom is a stub.