Prior to the formation of the band, lead vocalist Lydia Night met guitarist Genessa Gariano, bassist Sage Chavis, and drummer Maxx Morando in music school.

[11] In 2016, the band toured with both Tacocat and Sleigh Bells, opened for Kate Nash, and performed at South by Southwest.

[19] On May 22, 2018, the tour bus containing all their belongings was stolen from outside the Sunflower Lounge, Birmingham, UK where they later played a sold-out gig.

[19] On November 28, 2018, the band announced the departure of Mayugba and recruitment of Brooke Dickson as their new bass player.

[23] From February 6 to March 17, 2019, The Regrettes were the opening act of Twenty One Pilots' European leg of The Bandito Tour.

[30] Michael Bialas, a writer at PopMatters described their sound as "girl-group power-pop punk"[23] In an article by Culture Collide, their style was described as "Channeling classic doo-wop through a catchy garage-punk filter" and as bringing "a level of impassioned aggression to tried-and-true pop structures, creating a compelling product with significant crossover appeal.

[35] They also cite musical influences including Bikini Kill, L7, 7 Year Bitch,[36] Elvis Presley, Buddy Holly, The Ronettes, Hole,[37] The Crystals, Lesley Gore and Patsy Cline.