31 Ọgọọst bu ubochi nke 31st (nke iri atọ na out) na onwa ana kpo Ọgọọst. Na Gregorian calender, 31 Ọgọọst bu ubochi nke 243rd (244th na afo nke ana-kpo leap year) na afo. Anyi nwere agugu ubochi 122 du mgbe afo na agwu.