Chamber music with piano (organ)
Violin and piano
| 1864 | Romanze G major |
| Zum 30sten September 1864 (dem 35sten Geburtstag von Engelbert Röntgen) | |
| 1865 | Zum 17ten April 1865 |
| 1867 | Sonata D minor |
| 1873 | Sonata A major |
| 1876 | Adagio for violin and organ (zum Palmsonntag 1876) |
| 1877 | Zwei Stücke, E minor and A minor |
| 1879 | Variationen über ein nordisches Volkslied op. 21 (originally Variationen über ein norwegisches Volkslied for piano, 1879) |
| 1879-1883 | Sonata F-sharp minor op. 20 |
| 1882 | Schwedische Weisen und Tänze (by Julius Röntgen and Amanda Röntgen-Maier) |
| 1884 | Phantasie A minor op. 24 |
| 1885 | Duo A minor |
| 1892 | Canonische Suite |
| Aus Jotunheim (also for orchestra, 1892, for French horn and piano, 1902) | |
| 5 Canons | |
| 1897 | Oud-Hollandsche Boerenliedjes en Contradansen, 5 volumes |
| 1900 | Sonate E major op. 40 |
| 1904 | Oud-Nederlandsche Dansen op. 46b (originally Oude Nederlandsche Dansen for orchestra op. 46) |
| 1908 | Sonata F major (In Erinnerung an Edvard Grieg) |
| 1910 | Suite in Alt-Holländischer Weise |
| 1917 | Catrijper Sonata |
| Bellmannweisen | |
| 1917-1918 | 5 Morceaux for cello/violin and piano (revised 1922-1924) |
| 1920 | Romanze |
| 1924 | Sonata F minor |
| 1925 | 7 Vortragsstücke op. 89 |
| Sonata trilogica | |
| 1926 | Schüler-Konzert no. 1 D major op. 85 |
| Schüler-Konzert no. 2 G major op. 88 | |
| Een kermisboekje uit 1769 | |
| Sonate in zwei Teilen | |
| 1927 | Schüler-Konzert nr. 3 E minor op. 87 |
| 1929 | Suite naar Joh. Walthers Hortulus Chelicus |
| 1930 | Boerenliedjes uit een oud kermisboekje |
Viola and piano
| 1924 | Sonata C minor |
| 1925 | Sonata A-flat major |
| Sonata A minor |
Viola d 'amore and piano
| 1913 | Suite Bachiana (also for piano, 1913) |
Cello and piano
| 1872-1873 | Sonata B-flat major op. 3 |
| 1902 | Sonata A minor op. 41 |
| 1903 | Variationen und Finale über Sankt Nepomuk (originally for French horn and piano, 1903) |
| 1905 | Sonata G minor |
| 1906 | Sonata C minor |
| 1907 | Sonata B minor op. 56 |
| 1909 | Phantasie über irische Volkslieder (also for cello and orchestra, 1928) |
| 1914-1915 | Sonata D major |
| 1917 | Sonata F-sharp minor |
| 1917-1918 | 5 Morceaux for cello/violin and piano (revised 1922-1924) |
| 1926 | Sonata D minor |
| 1927 | Sonata E minor |
| Sonata C minor | |
| 1930 | Sonata D minor |
| Sonata A minor | |
| 1931 | Sonata C-sharp minor |
| Sonata C major | |
| 1932 | Variationen über ein Alt-Englisches Volkslied |
Wind instrument and piano
| 1902 | Aus Jotunheim, Suite über norwegische Volksweisen for French horn and piano (originally violin and piano, 1892) |
| 1903 | Variationen und Finale über Sankt Nepomuk for French horn and piano (also for cello and piano, 1903) |
| 1918 | Sonata 1 F-sharp minor for oboe and piano |
| 1928 | Sonata 2 D major for oboe and piano |
| 1929 | Sonata A-flat major for bassoon and piano |
Piano trio (violin cello piano)
| 1883 | Trio B-flat major op. 23 |
| 1898 | Trio D major Trio G minor |
| 1904 | Trio C minor op. 50 |
| 1919 | Trio A minor (Troldhaug) |
| 1921 | Trio F-flat minor (in one part) |
| 1924 | Trio F minor (Post Tenebras Lux) |
| Gaudeamus Trio A major | |
| 1932 | Trio G minor |
| Trio C minor | |
| Trio E minor | |
| Trio E-flat major | |
| Trio G minor |
Piano trio
| 1921 | Trio E-flat major für Clarinette, Bratsche und Klavier |
Piano quartet (two violins cello and piano)
| 1898 | Walzer (originally for piano four hands, 1884) |
| 1927 | De Hellevaart van Dr. Joan Faustus |
| 1928 | Rei van Helsche Vrouwengeesten |
Piano quartet (violin, viola, cello and piano)
| 1919 | Quartet A major |
| 1931 | Quartet G minor |
Piano quintets
| 1903 | Quintet C major (2 violins, viola, cello, piano) |
| 1911 | Quintett für Flöte, Oboe, Klarinette, Horn und Klavier |
| 1927 | Quintet in A minor op. 100 (2 violins, viola, cello, piano) |
| 1932 | Quintet G major (Sentendo nuova forza, 2 violins, viola, cello, piano) [final work, 5-7-1932] |