After the war Oakes rose to be Registrar-General of NSW Births Deaths and marriages and a member of the Public Service board.
Eventually joining the NSW Treasury in 1960, he rose to become the head in 1977 as Under Secretary and Comptroller of Accounts, the last to serve under that title.
[3] After his retirement in 1986 Oakes served as a Commissioner of the City of Sydney from its dismissal by the Unsworth Government on 6 April 1987 to 31 December 1988.
In later years he served the NSW Branch of the Red Cross, including as Honorary Treasurer, for which he was awarded the Centenary Medal in January 2001.
[4] In retirement, Oakes was an active member of the Yowie Bay Community and helped run a local Neighbourhood Watch program there for many years.