[17] Neil McCormick from The Daily Telegraph considered that Aguilera sounded "like a one-woman Fleetwood Mac" and praised "her rich low notes fluttering effortlessly up to falsetto with no loss of control".

[18] During a review for Liberation for PopCrush, Bobby Olivier called "Twice" "a sparse and pensive track" and described the intro of the song as "harmonic".

[19] Althea Legapsi from Rolling Stone opined that the lyrics contemplate "the duality that can be found with love",[20] and Mike Nied from Idolator deemed the singer's voice, calling it "as strong as ever before".

[22][23][24] It was meant to express the singer's thankfulness for her fans' support, and contains a spiritual, naturalist theme: Aguilera is seen submerged in water, and those scenes are followed by close-ups of flowers.

[4] The singer's rendition at the Radio City Music Hall on October 4, 2018 was called "killer" by The Star-Ledger's Bobby Olivier.

[31] In July 2021, Aguilera performed "Twice" during her two night show at the Hollywood Bowl with Gustavo Dudamel and the Los Angeles Philharmonic.