The name Charlotte rode a royal wave to become the most popular for girls in 2015, while Oliver reigned for baby boys.

After the Duke and Duchess of Cambridge – aka Wills and Kate – gave the name to their little girl in May, scores of parents in NSW did the same.

There were 529 newborns called Charlotte last year, pushing the name into top place after being pipped by Olivia in 2014. 

Oliver was the most popular boy's name in NSW for the second year running, bestowed on 607 babies in 2015. William, Jack, Noah and Lucas also made the top five, while Olivia, Mia, Amelia and Chloe were the other most popular names for girls.

The registrar of the NSW Registry of Births, Deaths and Marriages, Amanda Ianna, said names "will come in and out of vogue with special events, famous people, and political change". 

"Charlotte spiked in popularity following the birth of Princess Charlotte last year and we expect that trend to continue with 2016 being the 200th anniversary of Charlotte Bronte's birth." 

A fortnight after the fourth in line to the throne was born, Sydney couple Sharon and William Lancaster had a baby girl. They had already settled on a name – Charlotte – and were not deterred by the royals' choice.

"It's such a lovely name and we didn't have any other girls' names picked," Ms Lancaster said. "She just looked like a Charlotte. I'm sure there's going to be a couple of others in her class at school."

Ms Ianna said NSW parents were favouring traditional names such as William and Jack that were popular a century ago. Social researcher Mark McCrindle said parents were opting for "the traditional over the trendy".

"Parents are looking for something solid and significant," he said. "They know  the name they're choosing becomes their email address and their website and their Twitter handle. They do need a name that's easy to spell, that's not too creative, that you don't have to explain all the time."