This series contains material relating to the Old Grantite Club, which was a group for alumnus of Grant's House. Members of the club paid a subscription fee to join which was used to fund social events organsied by the club as well as the production of the 'Grantite Review', the House magazine. The main event organised by the club was the annual dinner, although they also organised golf and cricket matches. This series contains the minute books of the club, lists of its members and publications by the club.

Begun by M. G. Hewins (G 1911 - c.1916) in Election term 1916, this volume is a list of old Grantites arranged alphabetically by surname in decades. Each Head of house was to add the names of those who left each year. Some names also have notes about the careers of the pupils after they left Westminster School. It is based on the work of Lawrence Tanner, Grant's House ledgers and school registers. There is a list at the back of the book of Old Grantites who died before the list was compiled and which are not included in the main register.

This series contains the Grant's House athletic ledger and water ledger, both of which include descriptions of sporting events and achievements. There is also a note book titled 'Grant's Station List' which records the boys' attendance at Station.