Reception
Box office
Little Black Book opened at number five at the North American box office, grossing $7,075,217 in its opening weekend behind Collateral, The Village, The Bourne Supremacy, and The Manchurian Candidate. The film ended its run with a domestic total of $20,698,668 and an international addition of $1,336,164, totaling $22,034,832 worldwide. Metacritic, which uses a weighted average, assigned the film a score of 36 out of 100, based on 33 critics, indicating "generally unfavorable" reviews. Audiences polled by CinemaScore gave the film an average grade of "B−" on an A+ to F scale.
Entertainment Weekly Scott Brown awarded Little Black Book a D, stating, "The big climax isn't climactic, just hysterical and incoherent. Murphy, with her bug-eyed, love-me mugging, is simply too slight and gawky to play the Everygirl." Similarly, Carla Meyer of the San Francisco Chronicle gave the film a poor review, criticizing the script and acting.
However, the film received some positive reviews; Andrea Gronvall of the Chicago Reader praised the film's humor, rating the film three and a half stars. Roger Ebert awarded the film three stars out of four and praised Murphy's performance.