Critical response
Roger Ebert of the Chicago Sun-Times gave the film four stars out of four, describing the film as "a delightful comedy, alive with invention". He particularly praised the strong performances of Gordon-Levitt and Deschanel and summarized his review by adding, "Here is a rare movie that begins by telling us how it will end and is about how the hero has no idea why". Premiere also awarded the film four stars out of four, stating "Much like the actual summer (the season, not the character), we never wanted it to end".
Michael Ordoña of the Los Angeles Times wrote, "(500) Days of Summer is something seldom seen: an original romantic comedy. It bristles with energy, emotion and intellect, as it flits about the dizzying highs and weeping-karaoke lows of a passionate entanglement".
Dana Stevens of Slate also praised the film and described it as "a keeper. It's fun both to watch and to talk about afterward, and it possesses the elusive rom-com sine qua non: two equally appealing leads who bounce wonderfully off each other".
Entertainment Weekly critic Owen Gleiberman gave the film an "A", and also praised the originality of the story; "Most romantic comedies have half a dozen situations at best: Meet Cute, Infatuation, Pop Song Montage, Contrived Mix-Up, Angry Breakup, and Final Clinch. (500) Days of Summer is about the many unclassifiable moments in between. It's a feat of star acting, and it helps make 500 Days not just bitter or sweet but everything in between". Film Threat critic Scott Knopf gave the film a maximum five stars, writing: "Of course they meet. Of course they fall for each other. Of course there are problems. It sounds cliché but what's remarkable about 500 Days is how the film explores new ways to tell the world's oldest story". He concluded that the film was "the best romantic comedy since Love Actually."
Peter Travers of Rolling Stone gave the film three and a half stars out of four. He wrote, "Boy meets girl, boy loses girl. It's been done to emo death. That's why the sublimely smart-sexy-joyful-sad (500) Days of Summer hits you like a blast of pure romantic oxygen" and concludes: "500 Days is otherwise a different kind of love story: an honest one that takes a piece out of you". USA Today's Claudia Puig wrote: "Much like Annie Hall did for a previous generation, (500) Days of Summer may be the movie that best captures a contemporary romantic sensibility."
IGN critic Eric Goldman gave the film 9 out of 10, and praised the film as "one of the best of 2009" and particularly complimented the innovative nature of the story in an often clichéd genre; "(500) Days of Summer proved there is a way to bring something fresh and new to one of the most cliché and often frustrating genres – the romantic comedy". A. O. Scott of The New York Times gave the film 4 out of 5 and called it "Slight, charming and refreshingly candid little picture."
Scott Tobias of The A.V. Club graded the film B−, criticizing it for its "dispiriting clichés," which make it "wind up in a no-man's land between Hollywood and something real." NPR was more dismissive: "For all its rhetorical whimsy and hipster dressings, (500) Days of Summer is a thoroughly conservative affair, as culturally and romantically status quo as any Jennifer Aniston vehicle."
Joe Morgenstern of The Wall Street Journal was also more critical, calling it, "synthetic and derivative, a movie that's popping with perceptions while searching for a style." British newspaper The Times gave a mixed review. Toby Young awarded the film three stars out of five, but conceded that "It is hardly the freshest romantic comedy of past 20 years. Taking the best bits from other movies and rearranging them in a non-linear sequence does not make for an original film." The Guardian film critic Peter Bradshaw said the film was "let down by sitcom clichés, and by being weirdly incurious about the inner life of its female lead."
Mark Adams of the Daily Mirror, though, gave the film a glowing review, awarding it five stars, and writing, "It is a modern romance for grown-ups... a sweet-natured, funny, deeply-romantic tale that brims with energy and is blessed with top-notch performances by Deschanel and Gordon-Levitt, who are both charming and have real chemistry". Empire gave the film 4 out of 5 stars, and wrote: "Perfectly played, simultaneously serious and light, endlessly inventive, this is a strong contender for the most original date movie of the year."
Since its release, the film has been considered a cult classic, and has been compared to other notable films such as Annie Hall (1977), and High Fidelity (2000). In 2025, it was one of the films voted for the "Readers' Choice" edition of The New York Times' list of "The 100 Best Movies of the 21st Century," finishing at number 230.
