Unbeaten Chess Records
William (Wilhelm) Steinitz (1836-1900) became world champion on March 29, 1886. As world champion, he played in 3 matches in Havana in 1888, and won 5 games against Andres Vasquez , won 5 games against Celso Golmayo Zupide, then lost to A. Ponce. Steinitz had 25 consecutive wins from 1873 to 1882. He was undefeated for 9 years and 283 days.
In 1892-1893, Emanuel Lasker (1868-1941) was unbeaten in 30 consecutive tournament games. He was unbeaten in the last 3 rounds of the 1892 British Chess Federation tournament. He was undefeated in 8 games at London 1892, undefeated in 5 games at Newcastle 1892 and 13 games at New York 1893. He won the first game against Showalter at Kokomo in 1893, but lost in the second game. From May 1904 to August 1908, Emanuel Lasker (1868-1941) was unbeaten in 27 tournament games. He did not lose the last 4 rounds at Cambridge Springs 1904. He did not lose any of his 6 games at the 1906 New York State championship. He did not lose any of the 15 games against Marshall in the 1907 world championship. He did not lose the first 2 games of the 1908 world championship. So the total is 27.
From 1914 to 1922, Alekhine was undefeated in 79 consecutive tournament games. He was undefeated in the last 5 rounds at Mannheim 1914. He was unbeaten in 11 games at Moscow 1915, unbeated in 6 games at Moscow 1918, unbeaten in 11 games in the 1919-1920 Moscow championship, unbeaten in 15 games in the 1920 All Russian championship, unbeated in 8 gams at Triburg 1921, unbeaten in 11 games at Budapest 1921, unbeaten in 9 games at The Hague 1921, and unbeaten in the first 3 games at Pistyan 1922.
In 8 years, from 1916 to 1924, Capablanca was unbeaten in 63 games.
Capablanca did not lose in 15 games at London 1922. He did not lose in the first 4 rounds of New York 1924 (he lost the 5th round against Richard Reti). So the total is 19 consecutive games undefeated. If you count the world championship match with Lasker in 1921, he did not lose any of the 14 games played, making the total of 33 consecutive games unbeaten.
Vera Menchik-Stevenson (1906-1944) was World Women’s Chess Champion from 1927 to 1944. She defended her title 6 times. In world championship play, she won 78 games, drew 4 games, and only lost once (to W. Henschel at Hamburg in 1930). She lost 1 game out of 83 world championship games.
As world champion, Alekhine did not lose the last 7 games of his 1929 world championship match with Bogoljubow. Then he went unbeaten in 15 rounds at San Remo 1930. Then we went unbeaten in 9 rounds at the 1930 Hamburg Olympiad. He then went unbeaten in 8 games at 1931 Nice. He then went unbeaten in the first 15 rounds at the 1931 Prague Olympiad, finally losing to Mattison in round 16. That makes 54 games unbeaten as world champion.
Mikhail Botvinnik became world champion on May 16, 1948. He did not play a single tournament chess game until the next world championship in 1951. Botvinnik was undefeated in the first four games before losing to Bronstin in the 5th game.
From 1967 to 1970, Fischer was unbeaten in 53 consecutive tournament games. He was undefeated in the last 5 games at Skopje 1967. He was undefeated in 10 games at Sousse 1967, undefeated in 13 games at Netanya 1968, undefeated in 13 games at Vinkovci 1968, 1 win at the New York Metropolitin League, undefeated in 4 games at the 1970 USSR vs Rest of the World match, and won the first 7 rounds at Rovinj/Zagreb before losing to Kovacevic in round 8. Fischer won 20 straight games from 1970 to 1971 against some of the strongest players in the world.
From July 1972 to April 1973, Mikhail Tal was unbeaten in 86 tournament games. During that period, he won 47 games and drew 39.
Between October 23, 1973 to October 16, 1974, Mikhail Tal was unbeaten in 95 tournament games. During that period, he won 46 and drew 49. He lost to Kirov at Novi Sad on Oct 16, 1974.
Karpov became world chess champion on April 3, 1975 after Fischer forfeited. Karpov played 29 consecutive games as world champion before losing. He played 15 games without a loss at Ljubljana-Portoroz in 1975. Then he played 7 games without a loss at the 6th USSR Spartakiad in Riga. He finally lost in round 8 against Ulf Andersson in Milan on Aug 28, 1975. He did not lose in the first 7 rounds.
Garry Kasparov became world champion in 1985. He then had to play Karpov in a return match in 1986. He was unbeaten after the first 4 games, then lost the 5th game to Karpov.
So far, after becoming world champion, Magnus Carlsen is unbeaten after 5 classical games, played at Zurich in January-February, 2014. He was unbeaten in 10 games at the world championship match against Anand in Chennai, India in November 2013. He was unbeaten in 6 games at the Sinquefield Cup in September, 2013. Carlsen won his last 6 games at the Tal Memorial in June 2013. He has now been undefeated in his last 27 games.
Bill Martz (1945-1983) played 104 consecutive USCF-rated chess games without a loss.