Belly ends up with Conrad in the conclusion of "The Summer I Turned Pretty" series. After a complex love triangle involving the Fisher brothers Conrad and Jeremiah, Belly ultimately chooses Conrad. The series finale shows Belly and Conrad reunited, expressing their love for each other and returning hand-in- hand to the beach house, marking a satisfying ending to their relationship. This aligns with the book's ending where Belly and Conrad get together and eventually marry, although the show's adaptation offers some expanded moments in Paris that deepen their reunion and love confession.