Schoolboy Rugby Union was introduced to Slough in 1948 by W J McLoughlin (a Welshman!) one time of Pontypridd and Cambourne and the Deputy Headmaster of The Technical School Slough. In 1961, the Old Students of the Technical School played against Slough RFC when Derek Lyon, later to captain Cambridge University in the Varsity Match of 1968 and 1969, first played for Phoenix.

The first Committee Meeting of Phoenix RFC took place on January 11th 1963 and the club played its first match against Old Windsorians (later to merge with Windsor) on November 9th of that year. Enthusiastic Club Secretary Bob Cobb arranged further fixtures and the Phoenix began to rise. During that embryonic year, Phoenix played against the then Old Pennanians, Thames Valley who became Maidenhead, Shire Hall, Beaconsfield and Slough.

Phoenix obtained their name as the result of a remark made by the then Head Master of Slough Technical School, A S Humpheryes, concerning the move of the school from the fire damaged ruins in William Street to the brand new school buildings in Northampton Avenue. In the early days, fixtures were played on the Godolphin field, using the nearby School for changing facilities and its Domestic Science room for tea. Players during those early years who made things happen included Norman Garrard (treasurer), Ron Jones (the first), Pete Kelso(scrum-half), Dave Tottingham(second row who always managed to injure someone), Dave Ward (Club Captain for some years, now in Canada), Garry Martin(Captain), Chris Mitchell, Lionel Buckman, Alan Bunting, Jim Pecover, Ian Lumley, Brian Miles, John Lewer, Ray Castle, Mick Brench, Malcolm Wells and Steve Rafferty.