Most of its original eighty-five pupils lived in the city within walking distance of the school.

During the early Victorian Era, members of the teaching staff included Gabriele Rossetti, who taught Italian.

By 1843 there were five hundred pupils and the need for larger premises eventually led to the move to Wimbledon in 1897.

In 1882, only Eton College surpassed the total of thirty Oxford and Cambridge Board examination certificates obtained by pupils at KCS.

In 1897, falling numbers of pupils prompted the move to the school's present site in Wimbledon, a suburb served by the railway lines from Surrey and south London.

GCSE summary: 2018–2024[4] A level summary: 2018–2024[4] International Baccalaureate Results: 2018–2024[4] KCS occupies a 20-acre site on the south side of Wimbledon Common and owns a boathouse on Putney Embankment and two additional playing-fields in Raynes Park and Motspur Park.

[14] King's has supported the Shanghai-based education provider Dipont in establishing schools in China.

King's College International School Bangkok opened in September 2020 to over 300 boys and girls aged 2–10.

In the senior school the medium of instruction is English, offering IGCSEs in years 10 and 11 and the IB Diploma programme in the sixth form.

[27] The Warrant of the Lodge was issued on 23 February 1921 and it was consecrated at Freemasons' Hall, London, on 3 May 1921.