Reiss was the son of the lawyer, composer, and musicologist Georg Reiss and Elisabeth Dymling (1861–1920). He was the brother of the pianist and cabaret performer Elisabeth Reiss and the father of the actor Helge Reiss. He played opposite his son in the 1970 crime comedy Skulle det dukke opp flere lik er det bare å ringe. His first marriage was in 1920 to Esther Colbjørnsen Dahl (1896–1941). After her death, he remarried in 1944 to Gunborg Kristiane Skistad (1911–2001).
