Think Tank received mostly positive reviews. At Metacritic, which assigns a normalised rating out of 100 to reviews from mainstream critics, the album received an average score of 83, which indicates "universal acclaim", based on 26 reviews. Drowned in Sound writer Andrew Future deemed the album "a genuine pleasure to behold" and whilst stating that previous albums Blur and 13 were "full of jump-start arrangements and fractured experimentalism", he described Think Tank as being "lush in melody, flowing in windswept electronica with a myriad of bombastic orchestral backing one minute, before retracting into cocoons of melancholic and clustered acoustics the next." Playlouder called the album "an extraordinary record that pushes boundaries and sets new standards." "The beat-driven tracks," observed Steve Lowe in Q, "veer towards the arty, white-boy-with-beatbox line of Talking Heads and The Clash (actually, the low-slung hip-pop of 'Moroccan Peoples Revolutionary Bowls Club' even recalls Big Audio Dynamite). Only the trudging, tedious six-minute squib 'Jets' really needs taking back to the shops." However, Stephen Thomas Erlewine of AllMusic wrote that the album "is the sound of Albarn run amuck, a (perhaps inevitable) development that even voracious Blur supporters secretly feared could ruin the band — and it has." He also described Think Tank as a "lousy album" on which the few strong tracks are "severely hurt by Coxon's absence".
