IT'S been their unofficial catch cry Down Under for decades.

And in a world first, McDonald's is making its much-loved moniker "Macca's" official.

The fast-food giant will change the signage on 13 selected outlets across the country in the lead up to Australia Day.

First will be the franchise at Engadine, in Sydney's Sutherland Shire, which will don the new Macca's slogan from today.

Chief marketing officer Mark Lollback said the move was a nod to the Australianism of the American takeaway.

"We've been a part of Australia for over 40 years now and we're incredibly proud to embrace our 'Australian-only' nickname," Mr Lollback said.

"What better way to show Aussies how proud we are to be a part of the Australian community than change our store signs to the name the community has given us.

"We've got restaurants right around the country joining in on this celebration of our Aussie nickname with Engadine in NSW and Kangaroo Point in Queensland kicking off the rollout today.

"From Wednesday, Victoria will have stores with the new signage just before South Australia and Western Australia join the party on Thursday."

In Sydney, the new signs will roll out at Brookvale, Bondi Beach, Gladesville, Glenmore Park and Thornleigh this week.

They will remain in place until February 4, when the traditional McDonald's signage will return.

Bondi Beach store licensee Glen Simmons said the change was a fitting tribute to the Australian way of life.

"My team at the Bondi Beach restaurant can't wait to see the new signs go up, we're extremely proud to be a part of the celebration of our Aussie nickname," he said. "We'll see the finished signs go up at our stores on Wednesday - it's going to be an exciting day for all of us."

Mr Lollback said the company had launched a formal bid to have "Macca's" listed in the Macquarie Dictionary.

McDonald's opened its first Australian store at Yagoona, in Sydney's southwest, in 1971 after a decade of success in the US.

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