Rania Aniftos of "Billboard" magazine said "Yummy" brings back "the flirtatious Bieber we've missed and been waiting for", describing the chorus as "catchy". Bryan Rolli, writing for "Forbes", said that Bieber "sings his heart out" on the song and noted although "the lyrics may not invite scholarly analysis ... Bieber sure does sound good singing them". Rolli concluded calling the song a "win, an inevitable chart smash" and opined that it is "sure to sound even better when 50,000 fans scream it every night on his upcoming tour". Mikael Wood of "Los Angeles Times" described the song as "a lithe little R&B number that faintly recalls Ginuwine's mid-'90s classic 'Pony' and basically three-and-a-half minutes of PG-13 sex talk seemingly directed at Hailey Baldwin". He stated that "though it's very cute, 'Yummy' feels awfully lightweight for a single that has as much hanging on it as this one does" and added that the song "loses much of its flavor after only a few spins".