Karl Anton August von Schleswig-Holstein-Sonderburg-Beck was born 10 August 1727 in Marburg, Hesse, Germany to Peter August von Schleswig-Holstein-Sonderburg-Beck (1696-1775) and Sofie von Hessen-Philippsthal (1695-1728) and died 12 September 1759 Stettin, Poland of unspecified causes. He married Friederike zu Dohna-Leistenau (1738-1786) 30 May 1754 in Königsberg, Russia.
Anton would have inherited the dukedom of Schleswig-Holstein-Sonderburg-Beck had it not been for his early death. His father Peter outlived him, so the dukedom was passed on from Peter to Anton's only son Friedrich.
Children
| Name | Birth | Death | Joined with |
| Friedrich Karl Ludwig von Schleswig-Holstein-Sonderburg-Beck (1757-1816) | 20 August 1757 Königsberg | 25 March 1816 Wellingsbüttel Manor | Friederike Amalie von Schlieben (1757-1827) |
Footnotes (including sources)
| ‡ General |