To get the 50c Big Macs, all customers need to do is just order the Big Mac via the MyMacca’s app.
The burgers usually sell for $6.55, which makes its a total of $6.10 savings.
The offer officially kicks off three months of never-seen-before promotions for the fast-food giant, which will see new menu items introduced from June until the end of August.
McDonald's opened its first restaurant in Australia in 1971, in Yagoona, NSW, and since then has operated 1009 restaurants nationwide, employing more than 107,000 people and serving two million Aussies every day.
The franchise has also sold over 1.1 billion Big Macs, 1.9 billion cheeseburgers, and hosted over 700,000 birthday parties since its first launch.
The new offer comes after McDonald’s recently announced a collaboration with Korean boyband BTS, with the launch including a meal of chicken nuggets, fries, and two limited-edition sauces.
Included was also a limited-edition collaboration merchandise line.
The BTS McDonald’s collaboration is part of the fast food chain’s Famous Order promotion which sees the company highlight celebrity's orders at McDonald's.