Swimmer Sophie Pascoe and sailor Naomi James were New Zealand's previous youngest recipients of the top honour, both being appointed Dames at age 29. Shot-putter Valerie Adams was 32; Susan Devoy and Edmund Hillary were both 34.
The previous reported youngest Dame in the empire was British sailor Dame Ellen MacArthur, for her record-breaking, solo circumnavigation of the globe when she was 28.
RNZ approached the Department of the Prime Minister and Cabinet, which confirmed Dame Lydia was New Zealand's youngest ever person to receive the top honour.
It was not able to confirm whether she was the youngest dame in the history of the Commonwealth.
Dame Lydia added the honour to her other titles gained this year: Olympic gold medallist, British Open winner and LPGA Hall of Fame inductee.
Speaking to reporters about being made a Dame Companion of the New Zealand Order of Merit in the New Year's Honours List, Dame Lydia said she was humbled and honoured.
"It feels odd; you don't grow up thinking you will have a Dame next to your name. It is an honour to be recognised by your country - those opportunities don't come to everyone."
She joked that her husband of two years, Chung Jun, had asked her about the title "Dame".
"And I was like, 'Yeah, call me Dame!'"
Announcing the honour, the Cabinet Office said: "Lydia Ko is New Zealand's most successful golfer with 30 professional victories, including having won three major championships, 22 LPGA tournaments, and three Olympic medals in her golfing career."
The citation pointed out Dame Lydia had won a gold, silver and bronze Olympic medal, "becoming the first golfer in the modern era to achieve all three medals at three different Olympic Games. Her victory qualified her for the LPGA Hall of Fame, the 35th and youngest inductee at age 27. She was the youngest person ever to win a professional golf tour event and youngest person ever to win an LPGA Tour event."
Despite those achievements, Dame Lydia said she had considered whether she deserved the honour when initially contacted.
"I thought, 'Do I deserve this?' The only other golfer is Sir Bob Charles, I am guessing. To be alongside people like Sir Bob is a real honour."
Dame Lydia said she could not have achieved as much in the competitive world of professional golf without hugely supportive family, friends and well-wishers.
And despite her huge year in 2024, she had set her sights even higher with new goals for 2025 and beyond.
"Paris (Olympics) was like a fairy tale. And 2024 was an unbelievable year, especially after I had struggled the year before. We had put in all the work but then had just a mediocre start of the summer.
"All those puzzle pieces came together, but despite that I felt the odds were very small at Paris.
"It was emotional knowing it would be my last Olympics. After I won, it felt like Cinderella with the glass slippers ... then winning the major two weeks later. It was a crazy time."
"That was one of my initial goals when I first started on tour. But I realised that winning one major is hard, winning five is harder, and winning the full circle... it is just a small group of people who have done that."
Dame Lydia, who has been back in New Zealand visiting friends and family and talking to Golf New Zealand, said she sometimes considers how much her life has changed since she was a schoolgirl playing at Pupuke, with her father setting up the hole flag for her, or her mother driving her to events around New Zealand.
"My life has changed drastically - when I came from Korea to New Zealand as a young girl, I knew just four letters of alphabet and I had those in the wrong order - ABDC.
"Growing up, I always wanted to be a pro golfer. I have been fortunate - not many people have that opportunity.
"I have had the highs and lows. Did I think then I would be sitting in this seat, being interviewed about being a Dame? No, probably not. Life is crazy."
She said she hoped golfing administrators could revive the Women's New Zealand Open tournament, which she had won three times.
The Open had not run since 2017, but Golf New Zealand said in September it planned to revive the tournament to help grow the sport - especially after Dame Lydia's success on the world stage.
And she would love to play - if her schedule allows.
Dame Lydia said she hoped her new title and seeing the likes of Dames Sophie Pascoe, Lisa Carrington and Val Adams achieve on a world stage would help inspire young women to take up professional sport.
But she said she was also inspired by the enthusiasm of her young fans.
"The biggest thing that intimidates people about golf is how time-consuming it is. So go to a golf driving range for 30 minutes. See if you like it. Test the waters. Play with family or a group of friends.
"Have fun."
Congratulations
New Zealand Olympic Committee chief executive Nicki Nicol said Dame Ko's sporting journey was remarkable.
"Dame Lydia is without a doubt one of New Zealand's greatest Olympians. From being the youngest world number one in golf history, to standing on the Olympic podium three times, she embodies the values of hard work, determination, and excellence that we hold close as New Zealanders."
Nicol said the damehood was a fitting recognition.
"Her success brings immense joy to fans both at home and abroad and we are extremely proud of her. Being based offshore, Dame Lydia is also an amazing ambassador for New Zealand, she is a proud Kiwi."
