Critical response
On the review aggregator website Rotten Tomatoes, 50% of 167 critics' reviews are positive, with an average rating of 5.5/10. The website's consensus reads: "The Strangers has a handful of genuinely scary moments, but they're not enough to elevate the end results above standard slasher fare." Metacritic, which uses a weighted average, assigned the film a score of 47 out of 100, based on 28 critics, indicating "mixed or average" reviews. Audiences polled by CinemaScore gave the film an average grade of "B−" on an A+ to F scale.
Unfavorable reviews included Roger Ebert's of the Chicago Sun-Times, who gave the film one-and-a-half stars out of four, saying: "The movie deserves more stars for its bottom-line craft, but all the craft in the world can't redeem its story." Bob Mondello of NPR said the film was "A sadistic, unmotivated home-invasion flick." Steven Rea of The Philadelphia Inquirer noted that "No one is getting at anything in The Strangers, except the cheapest, ugliest kind of sadistic titillation." Elizabeth Weitzman of the New York Daily News compared the film to 2007's Vacancy – a "comparison which does Strangers no favors. Vacancy director Nimród Antal gave us a pair of heroes who fought like hell to survive, becoming closer and stronger in the effort. Bertino's undeveloped protagonists are colossally stupid and frustratingly passive." Stephen Hunter of The Washington Post panned the film, calling it "a fraud from start to finish." Mick LaSalle of the San Francisco Chronicle, said the film "uses cinema to ends that are objectionable and vile," but admitted that "it does it well, with more than usual skill." Wesley Morris of The Boston Globe said of the director, "Bertino has the pretensions of an artist and the indelicacy of a hack. He tries to get under our skin with a pile driver." Stephen Whitty of The Star-Ledger opined of the film, "Unfolding with an almost startling lack of self-awareness, young filmmaker Bryan Bertino's debut is such a careful, straight-faced knockoff of '70s exploitation films that it plays like a parody."
The Oregonian's Mike Russell described the film as "Funny Games stripped of all the humor" and, though praising it for its sense of dread, added: "For a little over half an hour, the movie skillfully turns its hollow screws... but somewhere after that, the movie loosens its grip. In fact, it gets repetitive and a little silly, no matter how hard Liv Tyler works at being terrorized." Ed Gonzalez of Seattle Weekly, though also referencing director Michael Haneke's Funny Games, favorably noted the film's suspense and restraint: "Analog-man Bertino teases with the unknown until he's left no pimple ungoosed. Sometimes avoiding the synapse-raping bad habits of splat-packers Eli Roth and Alexandre Aja is its own reward; doing so without also submitting to Michael Haneke–style hand-slapping is nearly monumental." The Guardian's Peter Bradshaw awarded the film a two out of five star-rating, criticizing its editing and structure, though he conceded the film is "intermittently effective."
Among the positive reviews, Jeannette Catsoulis of The New York Times said The Strangers is "suspenseful," "highly effective," and "smartly maintain[s] its commitment to tingling creepiness over bludgeoning horror." Michael Rechtshaffen of The Hollywood Reporter called the film a "creepily atmospheric psychological thriller with a death grip on the psychological aspect." James Berardinelli of ReelViews gave the film 3 out of 4 stars, saying that, "This is one of those rare horror movies that concentrates on suspense and terror rather than on gore and a high body count." Scott Tobias of The A.V. Club said that "as an exercise in controlled mayhem, horror movies don't get much scarier."
Additional positive feedback for the film came from horror author Stephen King, who lauded the film in an article published on his official website, in which he reviewed it alongside M. Night Shyamalan's The Happening: "I can't imagine that anything in X-Files will match Liv Tyler's exchange with one of the masked home invaders in one particularly terrifying scene of The Strangers. 'Why are you doing this to us?' she whispers. To which the woman in the doll-face mask responds, in a dead and affectless voice: 'Because you were home.' In the end, that's all the explanation a good horror film needs." JoBlo.com reviewer Berge Garabedian also praised director Bertino for "building the tension nicely, with lots of silences, creepy voices, jump scares, use of songs and a sharp eye behind the camera, as well as plenty of Steadicam give it all more of a voyeuristic feel." Critic Kim Newman, writing for Empire magazine, remarked the film's retro style, noting: "Like much recent horror, from the homages of the grindhouse gang through flat multiplex remakes of drive-in classics, The Strangers looks to the '70s", and ultimately summarized it as "an effective, scary emotional work-out." Slant Magazine's Nick Schager listed The Strangers as the 9th best film of 2008.