He served as the rabbi of the Jewish community in Florence, Italy from 1901 and also headed the rabbinical school in Florence. Subsequently and until 1918, Hayot served as a rabbi in the city of Trieste.
From 1918 to his death, Chajes served as the chief rabbi of the Jewish community of Vienna. In addition, he was also the Chairman of the Zionist General Council from 1921 to 1925.
Chajes died in Vienna in 1927. His remains were later taken to Israel and he was reburied in the Trumpeldor cemetery in Tel Aviv. The main Jewish school in Vienna is named after him.