Australia will have 40,000 centenarians in 40 years' time, the Intergenerational Report projects.
In a development which will put to the test Buckingham Palace's ability to dispatch congratulatory messages to all of the centenarians in the Commonwealth, the nation's ranks of 100-year-olds will increase nine-fold over the next four decades.
In 2055, the nation's 100 club is expected to be more than 300 times the size it was in 1975, when Australia had about 120 centenarians.
Former Australian of the Year Ita Buttrose said medical advances and healthier lifestyles would help the centenarians of the future enjoy their old age.
"Just because you're older doesn't mean you're ailing," she said.
"We've got to look at some positives here. I know lots of people who are working and they're past 60, past 65, past 70 even, and they're fit and they're well and they're enjoying life and they're active, so their brain's in good shape. Stop seeing ageing as some dreaded place - it's not. It's a new chapter, and what makes it so exciting is that it's unknown to a lot of us. We can wonder what it might be like, but we can never quite be sure."
Ms Buttrose said the demographic shift would produce greater demand for residential aged care, and the challenge for nursing homes was "to get over the image that so many people have of them of not being a place to which people want to go."
"If you look at some of the modern facilities that are being built, they're fantastic. They have to get across to people that there's big changes going on in residential aged care, and that the lifestyle can be enjoyable and something to look forward to."
She predicted the growth of older people as a proportion of the population would force designers of communities and products to pay more attention to seniors' needs.
"Lighting in public places is often not strong enough for older eyes. Bottles that are difficult to open, zippers on the back of dresses - it sounds funny but they're all sorts of things that affect people as they get older," she said.
Over the next four decades, the number of Australians aged 85 years or over is projected to quadruple to 2 million. This age group will represent almost 5 per cent of the population, up from 2 per cent today.
While the report projects life expectancy will rise only modestly over the next 40 years, to 95 for men and almost 97 for women, it raises the possibility of medical breakthroughs lifting life expectancy above 140 years.
Ms Buttrose said the challenge for governments was to encourage people to live healthier lives to reduce their risk of diseases such as dementia in old age.
Melbourne centenarian Lily Stein's mind remains sharp, even as her physical abilities fade.
The Emmy Monash Aged Care resident, who was born in Germany in 1914, and migrated to Australia in the 1960s, is still active, taking part in seated Zumba each Friday.
Mrs Stein's mother, Selma, instilled the motto "you only have your health once" into her daughter, but was not afforded the opportunity to reach 100 herself after she died in the holocaust.
Asked for advice on how to reach triple figures, Mrs Stein said did not presume to tell others how to reach a milestone she hadn't planned upon.
"It's up to you to enjoy your life. You make your life. No one else does," she said.
