John Montgomery Templeton CMG (20 May 1840 – 10 June 1908) was a Scottish Australian businessman and the author of non-forfeiture clause in life assurance policies.
In 1884 he left life assurance to become one of the three commissioners under the Public Service Act of 1883, appointed to establish the principle that promotion should depend on merit and seniority.
It was published with additions in March 1901 under the title The Consolidation of the British Empire, the Growth of Citizen Soldiership, and the Establishment of the Australian Commonwealth.
He was elected to the Victorian Legislative Assembly seat of Benalla and Yarrawonga at an 1893 by-election, and received the same number of votes as the other candidate, Thomas Kennedy.
Templeton was declared the winner on the returning officer's casting vote, and Kennedy then petitioned the clerk of the Legislative Assembly against the return, citing electoral irregularities and Templeton's position in the colonial militia and as an official liquidator possibly representing an office of profit under the crown.
His work in connexion with citizen defence was important, but his introduction of the non-forfeiture principle into life assurance policies was much more so.