Kate Buss was born in Sittingbourne, Kent, England on 28 December 1875, later being baptised on 5 March the following year.

She was the daughter of James Buss (1845-1936) and Elizabeth Hannah Brown (1849-1922), Kent natives who had married in Sittingbourne on 5 April 1871. Her father, a grocer, had been born in Pluckley, Kent in 1845, the illegitimate son of Mary Ann Buss. Her mother Elizabeth was born in Sittingbourne and, by coincidence, had been baptised on 14 April 1850.

One of eight children, Kate's siblings were: Edward James (1871-1872), Annie(1) (b. 1873, later Mrs Caleb Stephen Waite), twins Emma (1874-1897) and Edith (1874-1944), Elizabeth (1877-1900), Percy James (1882-1947) and Alfred George Albany (1884-1901).

Kate first appears on the 1881 census when she and her family were residing at 68 Shortlands Road, Sittingbourne. By the time of the 1891 census the family had relocated to 171-173 East Street, Sittingbourne and her father was by now described as a grocer and postmaster; Kate, aged 15, had already left school and was described as a postmaster's assistant. The family would have returned to 68 Shortlands Road by the time of the 1901 census and forwarding to the 1911 census they were living at 69 Bayford Road.

Kate was absent from the family home by the time of the latter record and she and her brother Percy were recorded elsewhere, their address being given as the Grocer & Draper, The Mart, Upper Halling, Kent with Kate being described as a drapery manageress. She was well known in the village and residents remember her preparing her trousseau and gathering together the wedding presents to take to America for her marriage to Samuel Willis in San Diego, California. Samuel George Willis (b. 13 October 1873) also hailed from Sittingbourne and was the son of a tailor and outfitter. He migrated to California around 1907/1908 where he worked as a carpenter and decorator.

Kate booked passage on the Titanic and joined the ship at Southampton (ticket number 27849 which cost £13) and was seen off by her brother Percy and a Mr Hedley Peters who had arranged her ticket; aboard she occupied a cabin on E-deck. After exchanging her ticket for a luncheon card Kate took her seat at the lunchtime dining table and here she met some of her fellow travelling companions, among them Dr Ernest Moraweck, whom she described as "very agreeable" and who proved his medical skill by removing some soot that had got in her eye. Moraweck offered to show Kate around New York once they arrived but she declined. Later that day, while on deck she met and shared a steamer rug with Marion Wright and the two became friendly. She also became acquainted with Susan Webber, Ethel Garside, Lucy Ridsdale and Reverend Ernest and Lillian Carter.
On the journey from Southampton to Queenstown she wrote a letter to her brother, Percy, using headed paper from the Titanic.

In other letters Kate described the pleasure she gained from the orchestra, in particular the cellist (probably John Wesley Woodward) whom she noticed that every time he finished a piece he would smile at her. In one letter she described two young girls travelling second class, believed to have been the multiracial Simonne and Louise Laroche: "There are two of the finest little Jap[anese] baby girls, about three or four years old, who look like dolls running about."

On Sunday 14 April Kate joined about a hundred other passengers in the second class dining saloon for a service led by Reverend Ernest Carter and she noticed that people sang the hymns with great emotion and that some had tears in their eyes.

Kate had retired and lay in her bunk reading a newspaper when the collision occurred at 11:40 pm and she recalled that it sounded like a skate on ice. She waited and listened to the engines reversing and when they stopped she went out in the hallway where she met her table companion Dr Ernest Moraweck who offered to investigate. Kate then went to the cabin of Marion Wright and awakened her and together they went on deck.

On deck there was little activity but they met Robert Douglas Norman who told them the ship had hit an iceberg. Whilst waiting they looked over the aft rail into the well deck where steerage passengers were beginning to congregate, many carrying all their belongings. Kate berated a passenger who scoffed at how protective they were being of their property, telling him that those trunks might contain all they had in the world. Before an argument could develop Robert Norman diffused the situation and guided the ladies below for some warm clothes.

As the boats were being loaded Kate turned away as she couldn't bear to watch the evacuation. She, Marion and Robert Norman discussed their chances of rescue. A little while later she got into boat number 9. But Douglas Norman was prevented—despite Kate's protests—from boarding.
When the boat reached the Carpathia she was the last to leave the lifeboat as she was frightened of heights and didn't like the thought of climbing the rope ladder up to the deck.

When the Carpathia reached New York Kate was alarmed that passengers without people to meet them would be taken to Ellis Island (although none were) and for this reason she stepped off the ship into the crowd. She and Susan Webber were eventually taken to the Junior League House, a hostel for women and was later taken under the wing of Rev S. Halstead Watkins chaplain to the Port of New York to whom the vicar of Sittingbourne had written. Kate applied to the American Red Cross for relief and was awarded $250 (record No. 60) and was quick to write to her family back in England to reassure them of her safety to warn them not to believe everything that they were reading in the papers about the disaster. In months after the disaster she maintained contact with several other survivors, including Susan Webber and Marion Wright.

Kate Buss eventually reached San Diego where she and her fiancé Samuel Willis were married on 11 May 1912. Their only child, a daughter, was born in San Diego on 4 February 1913 and named Sybil Lillian in honour of Mrs Lillian Carter.

Kate found her new homeland difficult to adjust to and she and her family initially made their home in San Diego; her sister Annie later joined her in America which made her feel more comfortable. By 1920 the Willis' home address was 7451 Prospect Street, San Diego and Samuel worked as a carpenter for Bates & Borley in Berkeley. At the time of the 1930 census they were living in Santa Monica and their address by the time of the 1940 census was 1029 24th Street in that city. Following Willis' retirement he and Kate moved to Pasadena, California to be close to their daughter; Sybil had married in 1937, becoming Mrs David Gordon Lane, and had a son, Ronald Willis (b. 1940).

Kate became a widow when Samuel Willis died on 4 February 1953, his daughter's birthday; their home address at the time was 1617 North Holliston Avenue, Pasadena. She followed her daughter to Oregon where she remained for the rest of her life. In later years Kate was never able to discuss the Titanic without becoming emotional, preferring to talk about the people she met aboard the ship than focus on the tragedy itself.

Kate spent her final days in a nursing home in Dallas, Polk, Oregon and died on 12 July 1972 aged 96; she was buried in Fircrest Cemetery in Monmouth, Oregon.

Her daughter Sybil died in Modesto, California on 24 September 2007.