Mr William Moss was born in Cotham, Nottinghamshire, England on 14 August 1876.

He was the son of William Moss (b. 1843), a domestic groom and gardener, and Mary Cutton (b. 1844), natives of Whatton and Flintham, respectively, who had married in 1870. 

The fourth of five children, William’s siblings were: Mary (b. 1871), Kate (1873-1873), Robert George (b. 1875) and Frank (b. 1878).

Moss appears on the 1881 census living with his family at an unspecified address in Cotham. Sadly, his mother passed away shortly after aged 37 and his father was remarried the following year to Betsy Caunt (b. 1853 in Elston, Nottinghamshire). From that union William gained three half-brothers: Herbert (b. 1885), John (b. 1888) and Harry (b. 1890) and the family moved to Grantchester, Nottinghamshire. On the 1891 census only William's sister Mary is shown living at their family address, Paradise, in that parish; William shows up as a visitor to an address in Balderton, Nottinghamshire, namely Horn Lane, the home of a Mr Lewis Hatfield and his family but he had no stated profession. His father died sometime around 1893.

When William went to sea is not certain but he had worked for the White Star Line for over a decade and had served aboard both the Cymric and Majestic between the years of 1901 and 1907.

He was married in Kelvin, Glasgow, Scotland in early 1905 to Susan Campbell Longmuir (b. 1880). Susan had been born in Crieff, Perthshire, the daughter of coachman William Longmuir and the former Elizabeth Wardrop, but spent most of her life living in Glasgow. 

William and Susan moved to Liverpool and whilst there welcomed their first child, Elizabeth Mary, who was born before the close of 1905; at the time of their daughter's baptism at St Michael's Church, Toxteth on 7 January 1906, they were living at 19 Lisburn Road in that locale and William was described as a seaman. The family's last known address in Liverpool was 38 South Front before they relocated to Southampton, likely to coincide with the movement of White Star's main port.

William would be absent from the 1911 census and likely at sea but his wife and child were listed as living at 37 Charlton Road, Freemantle, Southampton.

Moss was on board the Titanic for her delivery trip from Belfast to Southampton and when he signed-on again in Southampton for the maiden voyage on 4 April 1912 he gave his address as 37 Charlton Road, Southampton. His previous ship had been the Olympic and as a first class saloon steward he received monthly wages of £6. 

William Ward mentioned William Moss in his Senate Inquiry testimony, referring to him as the Head Waiter:

When I felt the shock, sir, I got up. I went to the port and opened it. It was very bitterly cold. I looked out and saw nothing. It was very dark. I got back into my bunk again. Presently two or three people came along there where we were all situated and said she had struck an iceberg, and some of them went and brought pieces of ice along in their hands. I thought at first it was the propeller gone, the way she went. I lay there for about 20 minutes, and in the meantime the steerage passengers were coming from forward, coming aft, carrying lifebelts with them. Some of them got their grips and packages and had them with them, and some were wet. Still I did not think it was anything serious, and I lay there for some time, a little while longer, when the head waiter came down - Moss, his name was - and said we were all to go on deck and to put on some warm clothing before we went up, as we were liable to be there some time. With that I think most everybody in the "glory hole," as we call it, got dressed and went on deck. I just put on things to keep me warm, because I did not think it was anything serious.

William Moss died in the sinking and his body, if recovered, was never identified.

His wife Susan had been pregnant at the time of the sinking and in August 1912 she gave birth to a daughter and named her Wilhelmina Frances, in honour of her lost father. The family moved northwards back to Susan’s home in Scotland, settling in Glasgow. Susan never remarried and died in Glasgow in July 1946 aged 65.

William’s eldest daughter Elizabeth married in 1939 to George Kerr McLaughlan (1907-1979). She moved from Glasgow to Wales where she lived for some time close to her son Graham.

His posthumously-born daughter Wilhelmina married Gilbert McDougall in Glasgow where they brought up their family of Kenneth, Alan, and Susanne.  After her husband's death in 1976 Wilhelmina stayed on in Glasgow for a number of years before moving to Stirling to be close to Susanne.  She died in Stirling in December 2004, aged 92