Korda made a film with Gyula Zilahy, The Duped Journalist (1914). He also directed Tutyu and Totyo (1915), The Officer's Swordknot (1915) and Lyon Lea (1915).

He followed it with The Grandmother (1916), Tales of the Typewriter (1916), The Man with Two Hearts (1916), The One Million Pound Note (1916), Cyclamen (1916), Struggling Hearts (1916), The Laughing Saskia (1916), Miska the Magnate (1916), St. Peter's Umbrella (1917), The Stork Caliph (1917) (from the novel by Mihály Babits), and Magic (1917).

Korda later regarded Harrison and Barrison (1917) as his best film. He also made Faun (1918), The Man with the Golden Touch (1918), and Mary Ann (1918).

In October 1919, Korda was arrested during the White Terror that followed the overthrow of the short-lived Communist government, the Hungarian Democratic Republic, because of his participation in its government. After his release, he left Hungary for Austria, and never returned to his country of birth.

After leaving Hungary, Korda accepted an invitation from Count Alexander Kolowrat to work for his company Sascha-Film in the Austrian capital Vienna. Korda worked alongside Kolowrat, who had attracted several leading Hungarian and German Directors into his employment, on the 1920 historical epic The Prince and the Pauper. The film was a major international success and inspired Korda with the idea of making "international films" with global box office appeal.

By that stage, Korda had grown irritated with Kolowrat's interference with his work and left Sascha to make an independent film, Samson and Delilah (1922), set in the world of opera. The film was made on a lavish scale, with large crowd scenes. The lengthy shooting schedule lasted 160 working days. The film was not a success.

Unable to find further backing for his film projects, Korda left Vienna and travelled to Germany. Korda raised funding for the melodrama The Unknown Tomorrow (1923).

With backing from Germany's biggest film company, UFA, Korda returned to Vienna to make Everybody's Woman (1924). While there, he began work on his next film, the historical Tragedy in the House of Habsburg (1924), which portrayed the Mayerling Incident. It earned back around half of its production cost. He followed this with Dancing Mad (1925), another melodrama.

In December 1926 after receiving a joint contract offer from the American studio First National, Korda and his wife sailed for the United States on board the steamer Olympic.

After The Stolen Bride's moderate success, Korda was brought in to work on the comedy The Private Life of Helen of Troy (1927), replacing the previous Director, George Fitzmaurice. The film retells the story of Helen of Troy, parodying the plot-line of historical epics of the era by transforming the classical characters into everyday people with modern problems. The film was a significant success for Korda, with his wife playing the role of Helen.

Korda's next few films Yellow Lily (1928) (with Dove), Night Watch (1928) (with Dove), and Love and the Devil (with wife Maria Korda(1929) were disappointments as his career lost its momentum. The latter two were both Silent films, but had sound effects and music added to their soundtracks as part of Hollywood's transitional phase of Technology following the success of the first Sound film The Jazz Singer.

Korda made two more sound films at First National: Her Private Life (1929) and Lilies of the Field (1930), both of which were remakes of earlier silent films.

A draft screenplay of what became The Red Shoes was written by Emeric Pressburger in the 1930s for Korda and intended as a vehicle for Merle Oberon, whom Korda later married. The screenplay was bought by Michael Powell and Pressburger, who made it for J. Arthur Rank. During the 1950s, Korda reportedly expressed interest in producing a James Bond film based upon Ian Fleming's novel Live and Let Die, but no agreement was ever reached.

Korda had a big success with Marius (1931)starring Raimu from the play by Marcel Pagnol. He followed it with Längtan till havet (1932), and The Golden Anchor (1932).

Korda then decided to form his own company. In 1932 Korda founded London Films with Big Ben as the company logo. Their first film was Wedding Rehearsal (1932). He produced Men of Tomorrow (1932) co directed by his brother Zoltan Korda, That Night in London (1932) starring Robert Donat, Strange Evidence (1933), Counsel's Opinion (1933), and Cash (1933).

Korda followed it with The Girl from Maxim's (1933) which he shot in English and French. He tried to repeat the success of Henry with The Private Life of Don Juan (1934) starring Douglas Fairbanks, which he directed, and The Rise of Catherine the Great (1934) which he did not. Neither did as well as Henry.

Korda produced a well respected short, The Private Life of the Gannets (1934) and enjoyed a big success as Producer with The Scarlet Pimpernel (1934). Also popular was Sanders of the River (1935) starring Paul Robeson and directed by his brother, and The Ghost Goes West (1936) starring Donat. His other credits as Producer include Moscow Nights (1936) with Laurence Olivier, Men Are Not Gods (1936), and Forget Me Not (1936).

Korda bought property in Denham, Buckinghamshire, including Hills House, and planned to build film studios on the property. London Film's Denham Film Studios was financed by the Prudential and opened in 1936. Korda was naturalised as a British subject on 28 October 1936. That same year, Korda was an important contributor to the Moyne Commission, formed to protect British film production from competition, mainly from the United States. Korda said: "If American interests obtained control of British production companies they may make British pictures here but the pictures made would be just as American as those made in Hollywood. We are now on the verge of forming a British school of film making in this country."

Knight Without Armour (1937) with Donat and Marlene Dietrich was an expensive epic that failed to recoup its money. The Divorce of Lady X (1938) was a comedy with Olivier and Merle Oberson.

Korda had a big success with The Drum (1938), directed by Zoltan and starring Sabu. He produced South Riding (1938), The Challenge (1938), The Rebel Son (1939) and Prison Without Bars (1938).

Korda, though, soon had financial difficulties and management of the Denham complex was merged with Pinewood in 1939, becoming part of the Rank Organisation.

The Winslow Boy and Fallen Idol were hits. An Ideal Husband and Anna Karenina had some acclaim but lost money. Bonnie Prince Charlie was a fiasco. Korda was also badly hurt by the trade war between the British and American film industries in the late 1940s. Korda did recover, in part due to a £3 million loan British Lion received from the National Film Finance Corporation.

While in the United States, Korda produced and directed That Hamilton Woman (1941) with Laurence Olivier and Vivien Leigh, and produced Lydia (1941) with Oberon.

On 22 September 1942, Korda was knighted at Buckingham Palace by George VI for his contribution to the war effort, the first film Director to receive the honour.

He returned to Britain in 1943 as production chief of MGM-London films, with a £35 million, 10-year programme. The scheme ended after one year, one film and a £1million loss to MGM.

The only film to come out of it was Perfect Strangers (1945) with Robert Donat and Deborah Kerr, which was popular. Korda directed.

Via London Films, Korda bought a controlling interest in British Lion Films. He produced A Man About the House (1947).

In 1948 Korda signed a co-production deal with David O. Selznick. This resulted in The Third Man (1949) which was a huge success.

London Films made smaller budgeted movies: The Cure for Love (1949), The Happiest Days of Your Life (1950), The Angel with the Trumpet (1950), My Daughter Joy (1950),State Secret (1950), The Wooden Horse (1950), Seven Days to Noon (1951), Lady Godiva Rides Again (1951), The Wonder Kid (1951), and Mr. Denning Drives North (1951).

Cry, the Beloved Country (1951), directed by Zoltan, was acclaimed. The Sound Barrier (1952) from David Lean was a hit.

He helped Finance Outcast of the Islands (1952), Home at Seven (1952), Who Goes There! (1952), The Holly and the Ivy (1952), The Ringer (1952), Folly to Be Wise (1953), Twice Upon a Time (1953), The Captain's Paradise (1953), and The Story of Gilbert and Sullivan (1953).

Korda was married three times, first to the Hungarian Actress María Corda in 1919. They had one son, Peter Vincent Korda, and divorced in 1930. In 1939, he married the film star Merle Oberon. They divorced six years later. He married, lastly, on 8 June 1953, Alexandra Boycun (1928–1966), who survived him.

Korda helped make The Heart of the Matter (1954), Hobson's Choice (1954), The Belles of St Trinian's (1954), and The Teckman Mystery (1954), In 1954 he received £5 million from the City Investing Corporation of New York, enabling him to keep producing movies until his death.

His last film was Laurence Olivier's adaptation of Richard III (1955) and Smiley (1956).

Korda died at the age of 62 in London in 1956 of a heart attack and was cremated. His ashes are at Golders Green Crematorium in London.

After the death of his father Korda began writing film reviews to support his family. Korda changed his family name from Kellner to Korda—from the Latin phrase "sursum corda" which means lift up your hearts.