Critical response
In Austria, "local critics were underwhelmed", and the film ran for only a few weeks. The Viennese Arbeiter-Zeitung, although critical of a "not-too-logical plot", praised the film's "masterful" depiction of a "time out of joint" and the city's atmosphere of "insecurity, poverty and post-war immorality". William Cook, after his 2006 visit to Vienna's Third Man Museum, wrote: "In Britain it's a thriller about friendship and betrayal. In Vienna it's a tragedy about Austria's troubled relationship with its past."
Some critics at the time criticised the film's Dutch angles. C. A. Lejeune in The Observer described Reed's "habit of printing his scenes askew, with floors sloping at a diagonal and close-ups deliriously tilted" as "most distracting". Reed's friend William Wyler sent him a spirit level with a note stating: "Carol, next time you make a picture, just put it on top of the camera, will you?"
Upon its release in Britain and America, the film received overwhelmingly positive reviews. Time wrote that the film was "crammed with cinematic plums that would do the early Hitchcock proud—ingenious twists and turns of plot, subtle detail, full-bodied bit characters, atmospheric backgrounds that become an intrinsic part of the story, a deft commingling of the sinister with the ludicrous, the casual with the bizarre."
The New York Times movie critic Bosley Crowther gave the film a mixed review, stating that the film:
... for all the awesome hoopla it has received, is essentially a first-rate contrivance in the way of melodrama—and that's all. ... It doesn't present any 'message.' It hasn't a point of view. It is just a bang-up melodrama, designed to excite and entertain.
Nonetheless he also described it as "an extraordinarily fascinating picture" and that:
[Reed] brilliantly packaged the whole bag of his cinematic tricks, his whole range of inventive genius for making the camera expound. His eminent gifts for compressing a wealth of suggestion in single shots, for building up agonized tension and popping surprises are fully exercised. His devilishly mischievous humor also runs lightly through the film, touching the darker depressions with little glints of the gay or macabre.
A rare negative review came from the British communist newspaper Daily Worker, which complained that "no effort is spared to make the Soviet authorities as sinister and unsympathetic as possible."
In a 1997 book, Roger Ebert praised the film and wrote: "It was a rainy day in Paris in 1962, and I was visiting Europe for the first time. A little cinema on the Left Bank was showing The Third Man, and I went, into the humid cave of Gauloise smoke and perspiration, and saw the movie for the first time. When Welles made his entrance, I was lost to the movies." He added it to his canon of "Great Movies" and wrote, "Of all the movies that I have seen, this one most completely embodies the romance of going to the movies." In a 1994 episode of Siskel & Ebert, Ebert named Lime as his favourite film villain. Gene Siskel remarked that The Third Man was an "exemplary piece of moviemaking, highlighting the ruins of World War II and juxtaposing it with the characters' own damaged histories".
The film has a 99% rating on Rotten Tomatoes based on 96 reviews, with an average rating of 9.3/10 and the following consensus: "This atmospheric thriller is one of the undisputed masterpieces of cinema, and boasts iconic performances from Joseph Cotten and Orson Welles." Metacritic, which uses a weighted average, assigned the film a score of 97 out of 100, based on 30 critics, indicating "universal acclaim".
Akira Kurosawa cited The Third Man as one of his 100 favourite films.
Pauline Kael for The New Yorker later said that the film had an atmosphere of "baroque glamour and evil."