I Don't Want You Back received generally mixed reviews from music critics who found the production by-the-numbers and felt that his potty-mouth gimmick wore thin. Johnny Loftus of AllMusic found a lot of filler in the album but said that it is "still quite promising, especially with such a statement-making single."Entertainment.ie was mixed about the album's tracks with their depiction of women, concluding that "Eamon certainly has plenty of attitude and his album is undeniably good fun. But he also has a bit of growing up to do." Rob Kemp of Rolling Stone said he saw promise in Eamon through the album's competent R&B production and the track "I Love Them Ho's (Ho-Wop)," concluding that "you wonder if this modestly gifted kid has something special inside him that perhaps Kanye West or R. Kelly could coax out."
Sal Cinquemani of Slant Magazine found Eamon's talent on the album limited, saying that the tracks that don't mix his dirty mouth with Motown and doo-wop melodies aren't "clever or well-constructed enough to transcend the misogyny and double-standards put on whorish display." Despite praising Eamon's vocals, the album's beats and guest rap appearances, Caroline Sullivan of The Guardian found the swearing crooner gimmick throughout the album wearing thin before it even ended.Robert Christgau graded the album as a "dud", indicating "a bad record whose details rarely merit further thought." Elysa Gardner of USA Today criticized the album for its lack of humor or irony in the songs, saying that "Eamon makes Eminem look like a standard-bearer for feminists."
The album debuted at number seven on the Billboard 200 with first-week sales of 106,000 copies. It dropped to number nine in its second week with sales dropping 31% to 73,000 copies. It was certified Gold by the RIAA for selling 591,000 copies.