 It peaked at number two for 3 weeks and remained on the chart for 31 weeks, eventually being certified five-times platinum by the Australian Recording Industry Association (ARIA) for sales over 350,000 units.The song topped the New Zealand charts on January 7, 2019, where it was certified platinum by Recorded Music NZ (RMNZ).In Brazil, "Sweet but Psycho" was certified diamond by Pro-Música Brasil (PMB) for selling over 160,000 units.