Hipkins, 44, has promised a back-to-basics approach, focusing on the economy and what he described as the “pandemic of inflation”.
He will have less than nine months before contesting a tough general election, with opinion polls showing his Labor party trailing the Conservative opposition.
Governor General of New Zealand Cindy Kyro presided over the short swearing-in ceremony in front of his friends and colleagues after she had previously accepted Ardern’s resignation.
“This is the greatest privilege and responsibility of my life,” Hipkins said at the ceremony. “I am energized and excited by the challenges ahead.”
Carmel Sepuloni was also sworn in as Deputy Prime Minister, the first time a person of Pacific Island ancestry had assumed the role. She congratulated Hipkins and thanked him for the trust he had placed in her.
After the ceremony, Hipkins told reporters aside, “It feels pretty real right now.”
Hipkins is known to many by the nickname “Chippy”, befitting his cheerful attitude and skills as an amateur handyman.
He served as education and police minister under Ardern. He rose to prominence during the COVID-19 pandemic when he took on some kind of crisis management role. But he and other liberals have long eclipsed Ardern, who became a global icon of the left and exemplified a new style of leadership.
Ardern said last week she was resigning after more than five years in the role because she no longer had “enough in the tank” to do the job justice. “It’s that simple,” she said.
On Tuesday, she made her last official appearance as prime minister, saying she would miss people the most because they had been the “joy of the job”. On Wednesday morning, she was greeted in Parliament’s forecourt with hugs and farewells from dozens of former staff and admirers as she left the building.
Ardern plans to stay on as a backseat legislator until April to avoid a special election ahead of the country’s general election in October.
New Zealand’s head of state is Britain’s King Charles III and Kiro is its representative in New Zealand, although today the country’s relationship with the monarchy is largely symbolic.
Britain’s Prince William and his wife, Kate, thanked Ardern on Twitter “for your friendship, leadership and support over the years, not least at the time of my grandmother’s death. Sending you Clarke and Neve our best wishes. W&C”
Clarke Gayford is Ardern’s fiancé and Neve is their 4-year-old daughter.