Paper Towns received mostly positive reviews. Publishers Weekly said that "the title, which refers to unbuilt subdivisions and copyright trap towns that appear on maps but don't exist, unintentionally underscores the novel's weakness: both milquetoast Q and self-absorbed Margo are types, not fully dimensional characters." They also commented that the novel is "another teen pleasing read". Meanwhile, Kirkus Reviews praised the novel as "a winning combination." Similarly, School Library Journal said that "Q is a great social outcast main character who sometimes thinks a little too much, but is completely relatable. Though we only really see Margo for the first third of the book, the clues really create her character and give us the feeling she's a complex person. Finding out who Margo is through the things she left behind was a really great way to develop her character."
Furthermore, Rebecca Swain of Orlando Sentinel stated: "Paper Towns has convinced me that jaded adult readers need to start raiding the Teen's section at the bookstore. Green, who grew up in Orlando and uses the city as a backdrop for the story, taps into the cadence of teenage life with sharp and funny writing, but transcends age with deeper insights." Similarly, Chelsey G.H. Philpot, editorial assistant of The Horn Book Guide, commented that "the end breaks your heart, and yet it feels right." Meanwhile, Rollie Welch called Paper Towns "Green's best work" up to that point. Critics, such as Michael Cart, praise John Green for his symbolism and ability to synthesize imagination and reality: "Green ponders the interconnectedness of imagination and perception, of mirrors and windows, of illusion and reality." Nevertheless, there has been some criticism and objection towards the text. Robert Corwin of Arizona State University argues that "some readers may find the author's use of language and sexual content objectionable."