The sale comes months after a A$8.8 billion takeover of Ampol - formerly known as Caltex Australia - by Canada's Alimentation Couche-Tard was shelved as a result of the financial blow and plummeting fuel margins caused by the coronavirus crisis.
The country's biggest fuel supplier said the minority stake was in a newly created property trust which would own 203 convenience retail sites throughout Australia. The deal values the entire property trust at A$1.4 billion.
Property firm Charter Hall said in a separate release it will own a 2.45% stake in the Ampol portfolio.
Ampol said it would will retain a 51% stake while maintaining strategic and operational control of the convenience retail sites.
The property trust would receive A$77 million in rental payments from Ampol in the first year, Ampol added, saying it planned to use the net proceeds of A$612 million from the deal to reduce its debt amid uncertainty around COVID-19.
(Reporting by A K Pranav and Arpit Nayak in Bengaluru; Editing by Kim Coghill)