Carington was the second son of Robert Carrington, 2nd Baron Carrington, and his second wife the Hon. Charlotte Augusta Annabella, daughter of Peter Drummond-Burrell, 22nd Baron Willoughby de Eresby. He was educated at Eton and served in the Grenadier Guards, achieving the rank of Lieutenant-Colonel. He fought in the Egyptian Campaign of 1882 and was awarded a medal for his actions.
Carington was a Groom in Waiting to Queen Victoria from 1880 to 1882. He was acting Master of the Buckhounds from 1883 to 1884, Equerry to Queen Victoria from 1881 to 1901 and an Extra Equerry to King Edward VII from 1901 to 1910. He also served as Comptroller and Treasurer to the Prince of Wales (late King George V) from 1901.
In November 1901 he was invested as a Knight Commander of the Royal Victorian Order (KCVO), and the following January he received the Prussian Order of the Crown, second class, with star, when he accompanied the Prince of Wales on a visit to Berlin for the birthday of Emperor Wilhelm II. In 1910 he was sworn of the Privy Council.
Carington married Juliet Warden, daughter of Francis Warden, of New York, on 23 September 1871. They had no children. She died in November 1913. Carington only survived her by eleven months and died aged 69. Robert Wynn Carrington, 1st Marquess of Lincolnshire, was his elder brother and Rupert Carington, 4th Baron Carrington, his younger brother.
- Debretts House of Commons and the Judicial Bench 1881
- Leigh Rayment's Historical List of MPs – Constituencies beginning with "W" (part 2)[self-published source][better source needed]
- The London Gazette: . 22 February 1901.
- The London Gazette: . 19 November 1901.
- The London Gazette: . 24 December 1901.
- "Court circular" The Times (London). Saturday, 8 February 1902. (36686), p. 12.
- "Sir William H. P. Carington.". New York Times. 8 October 1914. Retrieved 8 August 2008.
- Hansard 1803–2005: contributions in Parliament by William Carington
|Parliament of the United Kingdom|
John Remington Mills
|Member of Parliament for Wycombe
(representation reduced to one member 1868)