NBC said in a press release Monday that Stefani and Minogue will take the stage during the TV special Dec. 31.
Carson Daly will host the special live from Times Square in New York. Amber Ruffin and Stephen "tWitch" Boss will co-host.
"Nothing will make me happier than to have a front row seat to watch 2020 disappear and usher in the hope for brighter days in 2021," Daly said.
"I'm excited to be with Amber and tWitch live in Times Square to broadcast the iconic ball drop to millions of viewers on TV, but will miss the revelers who can't attend live. Our diverse music lineup offers something for everyone in your family."
NBC's New Year's Eve 2021 will air from 10 to 11 p.m. EST and then break for local news. The show will return at 11:30 p.m. for the final countdown to the iconic ball drop.
The TV special will be preceded by New Year's Eve: Escape from 2020, an NBC News special hosted by Today co-hosts Hoda Kotb and Jenna Bush Hager. The special revisits moments from 2020 and will air from 8 to10 p.m. EST.
Stefani released "Let Me Reintroduce Myself," her first non-festive solo single since 2016, last week.