Among the repertoire for the standard string sextet (2 violins, 2 violas, and 2 cellos) are the following works:"List of Compositions for String Sextet." International Music Score Library Project. Retrieved 20 June 2013.
Ordering is by surname of composer.
Afanasyev, Nikolai String Sextet
Barvinsky, Vassily String Sextet (1914)
Bečan, Nejc (1984) Clownology (The Jester, Pierrot - the sad Clown, The Circus Clown)
Berezovsky, Nikolai String Sextet No. 1 String Sextet No. 2
Boccherini, Luigi 6 String Sextets, Op. 23 (1776)
Borodin, Aleksandr String Sextet in D minor
Børresen, Hakon String Sextet in G major, Op. 5 (1901)
Brahms, Johannes String Sextet No. 1 in B-flat major, Op. 18 (1860) String Sextet No. 2 in G major, Op. 36 (1864-1865)
Bridge, Frank String sextet in E-flat major (1906-1913)
Busch, Adolf String Sextet
Cissell, Luke String Sextet No. 1 (2019) String Sextet No. 2 (2019)
Davidov, Alexei String Sextet in E-flat major Op.12
Davydov, Karl String Sextet Op.35 (1879)
Dohnányi, Ernst von String Sextet W080 (1893/6/8)
Antonín Dvořák String Sextet A major, Op. 48, (B. 80) (1878)
Gade, Niels String Sextet in E-flat major, Op. 35
Geviksman, Vitali String Sextet (1960)
Glass, Louis String Sextet, Op.15
Glière, Reinhold String Sextet No. 1, Op. 1 (1900) String Sextet No. 2, Op. 7 (1902) String Sextet No. 3, Op. 11 (1904)
Hofmann, Heinrich String Sextet in E minor, Op. 25 (published 1874)
Holbrooke, Joseph String Sextet "Henry Vaughan" in D major, Op. 43/16 (1902)
Indy, Vincent d' Sextet for Strings in B-flat major, Op. 92
Kapp, Artur String Sextet (1951)
Koechlin, Charles Le portrait de Daisy Hamilton, Op. 140
Koessler, Hans String Sextet in F minor (published 1902)
Korndorf, Nikolai Mozart Variations for string sextet (1990)
Korngold, Erich String Sextet in D, Op. 10
Ledenev, Roman Elegiac Sextet for strings Op. 30 (1982)
Lewandowsky, Max String Sextet in C minor, Op. 5
Martinu, Bohuslav String Sextet H. 224 (1932)
Merikanto, Aarre String Sextet (1932) (reconstructed by Paavo Heininen, 1993)
Mosonyi, Mihály String Sextet in C minor
Mozart, Wolfgang Amadeus (sort-of): Grande Sestetto Concertante (1808 transcription of the Sinfonia Concertante for violin, viola and orchestra)
Penderecki, Krzysztof Ciaccona in memoriam Giovanni Paolo II (Ludwig) (2005)
Piston, Walter String Sextet
Rääts, Jaan String Sextet, Op. 98 (1997)
Räihälä, Osmo Tapio Blaze ("Roihu" for six cellos) (2014)
Raff, Joachim String Sextet in G minor, Op. 178 (1872)
Reger, Max String Sextet in F major, Op. 118
Rimsky-Korsakov, Nikolai String sextet in A major (1876])
Rubinstein, Anton Sextet for strings in D major Op. 97 (1876)
Schoenberg, Arnold Verklärte Nacht (Transfigured Night), Op. 4 (1899)
Schulhoff, Erwin Sextet for strings, (1920–24)
Spohr, Ludwig String Sextet in C major, Op. 140 (1848)See Edition Silvertrust, also Brown: Louis Spohr, a Critical Biography.
String Sextet in G major, Op. 20
Stanchinsky, Aleksei Sextet for strings
Strauss, Richard Sextet for strings from the opera Capriccio
Tchaikovsky, Pyotr Souvenir de Florence for string sextet, Op. 70 (1890)
Vasks, Pēteris Spring Sonata for string sextet (1987)
Waterhouse, Graham String Sextet, Op. 1 (1979/2013)
Wilm, Nikolai von String Sextet Op. 27
Wuorinen, Charles String Sextet (1989)Charleswuorinen.com
References
IMSLP category for string sextets for the usual lineup
See also List of triple concertos for violin, cello, and piano String instrument repertoire List of solo cello pieces List of compositions for cello and piano List of compositions for cello and orchestra List of double concertos for violin and cello