Individual national and city championships, for more details of points and players, please have a look in the section with the chronological year-by-year survey of all 1st Prizes of Viktor Korchnoi:

1st Prize chronology - www.chessdiagonals.ch - Viktor Korchnoi

Viktor Korchnoi (*1931-2016) in 2011 at age of 80 years and four months, Switzerland, current world record.

Incredible 51 years, Viktor Korchnoi (from 1960 USSR-ch to 2011 Switzerland-ch).

A Soviet stamp dedicated to the 1962 (XXX.) USSR Chess Championship. Photo: Wikipedia

• USSR champion, Leningrad 1960
• USSR champion, Yerevan 1962
• USSR champion, Kiev 1964/65
• USSR champion, Riga 1970
  
  All four times sole winner, 16 participations.
  
  Remember, it was incredible tough and prestigious to get the (sometimes shared) title of the USSR Championship, only Botvinnik (six titles plus a one-off Absolute Championship) and Tal (also six wins) have more national titles than Korchnoi; with Svidler leading clearly in the post Soviet-Union time, achieving to date incredible eight Russian Championships!
  
  An incredible chess trivia: Former World Champion Vladimir Kramnik played in several National Russian Championships over years, but has never won any.

Korchnoi and Gallagher decided the title of 2011 in a tie-break. The first rapid game ended in a win for the eminent octogenarian veteran; the second wasn't played as a draw in the match would have suited Korchnoi, who had the better tiebreak criteria. Photo: Alexandra Kosteniuk, published in WhyChess.com

• Swiss champion, Silvaplana 1982
• Swiss champion, Arosa 1984
• Swiss champion, Silvaplana 1985
• Swiss champion, Grächen 2009,
  after rapid play-off vs. IM Ekström
• Swiss champion, Leukerbad 2011,
  after rapid play-off vs. GM Gallagher
  
  All five titles alone, eight participations. Viktor Korchnoi was normally busy and of course he was simply too strong, that's why he did no longer participate from the mid-1980s until the late-2000s. Last national title with 80 yrs and 4 mths!!
  
  For the sake of the legality of the things, Viktor Korchnoi also did win the Swiss Champion title in Biel in 1979 but was not awarded it as stateless person by the Swiss Chess Federation. He never complained, it's forgotten.

• Netherlands champion, Leeuwarden 1977

Korchnoi scored eleven wins and two draws (versus Hartoch and versus Langeweg)

  1. Viktor Korchnoi 12 out of 13 points!!
  2. Jan Timman 8.5
  3. Jan Hein Donner 8.5
  4. Hans Ree 8
  5. Kick Langeweg 7
  6. Gert Ligterink 6.5
  7. Robert Hartoch 6
  8. Hans Böhm 5.5
  9. Cornelis van Wijgerden 5.5
10. Fredrik van der Vliet 5.5
11. John van Baarle 5.5
12. Paul van der Sterren 5
13. Paulus Boersma 5
14. Leonard Hofland 2.5 

• Viktor Korchnoi won also the Championship of Uzbekistan 1957
  and the Championship of Armenia 1959 (both hors concours)
  
  
• Trade Union Championship (Spartakiade Syndicates), Leningrad 1969
   
• Leningrad City Champion 1955 (17/19 points, three points ahead of Tolush)
• Leningrad City Champion 1957, with Seymon Furman (1920 - 1978)
• Leningrad City Champion 1964 (14/16 points, four points ahead of Osnos)
   
• Junior Champion of Leningrad City, Leningrad 1946
  
• Junior Champion of USSR, Leningrad 1947
• Junior Champion of USSR, Tallin 1948, with Iivo Nei (*1931)
   
• Various minor events, mostly exhibitions in Switzerland, and some minor junior & senior events, are not listed and not counted for the records of tournament wins. 

Senior Chess World Champion (btw.: Junior Chess World Championship is installed since 1951, no participation of Viktor Korchnoi *1931)

For GOLD at the Students Chess Olympiad in Uppsala (Sweden) 1956, see under team events.

For the World Chess Championship Cycles, see under International Tournaments and Matches respectively.