Walter Thomas Boothby was born in Docking, Norfolk, England on 13 August 1874 and later baptised on 13 September that year.

He was the eldest son of John Aubin Boothby (1847-1915) and Charlotte Rayner (1846-1932), Norfolk natives who had married in 1870; at the time of his birth, Walter's father was a member of the lifeboat crew at Hunstaton.

Walter was one of ten children and his siblings were: Alice Marian (b. 1871), Leah Norah (b. 1872), Percy Charles (b. 1877), Maud (b. 1879), Ada Maria (b. 1882), Alfred William (b. 1883), Edward Henry (b. 1886), Joseph Henry (b. 1889) and Mabel (b. 1894).

Walter first appears on the 1881 census and at the time he and his family were living in East Street in Docking. His father, at the time, was described as a grocer's assistant. A change is his father's profession to that of a gamekeeper perhaps propelled to family to living in Alconbury, Huntingdonshire and they show up at North Road in that village on the 1891 census. Another change of profession for his father to that of a domestic gardener to a Mr Guy Fenwick of Luffenahm Hall saw the family living in North Luffenham, Rutlandshire by the time of the 1901 census, having moved there around 1896, but Walter was absent and likely at sea.

As a young man Walter worked as a butler and valet to a Captain Shipley; he went to sea around 1897 with the Orient Line and ended up in Australia before accepting an appointment with the Union Castle Line. During this time he visited South Africa at the height of the Boer War and was aboard the Dunottar Castle when that ship went missing for a prolonged period due to a navigational error. He later worked for the Hamburg-American Line and was aboard the St Paul when she collided with the Gladiator during a snowstorm in April 1908. In 1911 Boothby was aboard Olympic at the time of the Hawke collision; unbeknownst to him at the time his brother Alfred, a naval seaman, was aboard the Hawke!

Walter was married in the Oakham district of Rutland in mid-1904 to Caroline Annie Tunnicliffe (b. 7 June 1881 in Braunston, Rutlandshire), a lady's maid residing in London as per the 1901 census; she was the daughter of Thomas Tunnicliffe, a tailor, grocer and beer retailer, and his wife Sarah, née Kirkland. She and Walter would have no children.

Walter shows up on the 1911 census living as a lodger at 50 Ivy Road, St Denys, Southampton (the home of a Mr and Mrs William Philpott) and he is described as a married ship's steward for the White Star Line.

When he signed-on to the Titanic, on 4 April 1912, Boothby gave his address as 50 Ivy Road, St. Denys. His previous ship had been the Olympic and as a bedroom steward, he received monthly wages of £3, 15s. Also serving aboard was an in-law John Puzey; Walter's sister Ada was married to Puzey's brother-in-law William Stone.

Contemporary media reports that Boothby had not been to visit his parents in Luffenham for some nine months but intended to do so after this voyage.
Walter Boothby died in the sinking; his body was recovered by the Mackay-Bennett (#107) and was buried at sea on 24 April 1912.

The following memorial appeared for both Boothby and Puzey in the Portsmouth Evening News on 14 April 1913:

BOOTHBY AND PUZEY--In loving memory of our dear brothers, Walter and Jack, who was (sic) drowned in the terrible Titanic disaster, April 14th, 1912. Sadly missed by Ada and Will.

His widow Caroline never remarried and she settled in Edmonton, London where she lived at 120 Bedford Road for many years and from where she worked as a school nurse and health visitor. She died on 15 November 1953.