The song was included in an essential summer playlist article hosted via Billboard. Writer Jason Lipshutz opined that "War Paint" features "playful instrumentation and some whip-smart lyrical passages." LAUREN KRUCZYK writing for The Huffington Post branded it an "empowered song."
Perez Hilton described the song as "fresh" and compared it to Rachel Platten's single titled "Fight Song." Ilana Kaplan of Vice magazine branded "War Paint" an "anthemic, liberating hit" which remained true to Fletcher's ethos. Glamour magazine's Alexandra Schwartz called it a "contagious, punky pop song" which went viral fast.