HMS Newbury was a Racecourse-class (or Ascot-class) minesweeper of the British Royal Navy, built in 1916 by A.

Following the outbreak of the First World War, the Royal Navy supplemented its very small force of minesweepers with civilian ships purchased or chartered, particularly trawlers or paddle steamers.

The paddle steamers proved successful, with their shallow draft reducing the hazards from mines, and it was decided to build a class of dedicated paddle minesweepers, the Racecourse- or Ascot-class, with 24 ships ordered between September 1915 and January 1916.

[3][5] An inclined two-cylinder compound steam engine fed by cylindrical boilers drove the paddles.

The machinery was rated at 1,500 indicated horsepower (1,100 kW) giving a speed of 14.5 knots (16.7 mph; 26.9 km/h).