| Costello | Jno. | Pensioner | Bunbury | 1885 | Herald Almanack |
| Costello | Jno. | Pensioner | Wellington District | 1886 | WA Almanack |
| Costello | Jno. | Pensioner | Bunbury | 1887 | WA Almanack |
| Costello | Jno. | Pensioner | Bunbury | 1888 | WA Almanack |
| Costello | Jno. | Pensioner | Bunbury, Etc. | 1889 | WA Almanack |
| Costello | John | Tidewaiter | Bunbury | 1875 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury | 1875 | WA Almanack |
| Costello | John | Tidewaiter | Bunbury | 1876 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury | 1876 | WA Almanack |
| Costello | John | Tidewaiter | Bunbury | 1877 | Herald Almanack |
| Costello | John | Tidewater | Bunbury | 1878 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury & Suburbs | 1879 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury & Suburbs | 1880 | Herald Almanack |
| Costello | John | TideWaiter | Bunbury | 1881 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury | 1882 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury | 1883 | Herald Almanack |
| Costello | John | Tidewaiter | Bunbury | 1884 | Herald Almanack |
| Costello | John | Blacksmith | Bunbury | 1885 | Herald Almanack |
| Costello | John | | Bunbury | 1897 | Witton's Directory |
| Costello | M. | Carpenter | Geraldton | 1880 | Herald Almanack |
| Costello | M. | Carpenter | Albany | 1887 | WA Almanack |
| Costello | M. | Carpenter | Albany | 1888 | WA Almanack |
| Costello | M. | Carpenter | Albany | 1889 | WA Almanack |
| Costello | Martin | Carpenter | Albany | 1881 | WA Almanack |
| Costello | Martin | Carpenter | Albany | 1882 | WA Almanack |
| Costello | Martin | Carpenter | Albany | 1884 | WA Almanack |
| Costello | Miss | Schoolmistress Catholic Assisted School | Bunbury | 1877 | WA Almanack |
| Costello | Miss | Caterer | High Street, Fremantle | 1897 | Witton's Directory |
| Costello | Miss. | R.C Schoolmistress | Bunbury | 1877 | Herald Almanack |
| Costello | Miss. | R.C. Schoolmistress | Bunbury | 1878 | Herald Almanack |
| Costello | Mrs. E. | | Newman Street, Fremantle | 1897 | Witton's Directory |
| Costello | W. | Cabinet Maker | Perth | 1882 | WA Almanack |
| Costello | W. | Cabinet Maker | Perth | 1884 | Herald Almanack |
| Costello | W. | Cabinet Maker | Perth | 1884 | WA Almanack |
| Costello | W. | Cabinet Maker | Perth | 1885 | Herald Almanack |
| Costello | W. | Cabinet Maker | Perth | 1886 | WA Almanack |
| Costello | W. | Cabinet Maker | Perth | 1887 | WA Almanack |
| Costello | W. | Cabinet-Maker | Perth | 1888 | WA Almanack |
| Cot | Abraham | | 81 Howick Street, Perth | 1897 | Witton's Directory |
| Cotter | W. J. | Chemist & Druggist | Hannan Street, Kalgoorlie | 1897 | Witton's Directory |
| Cottle | R. | | Victoria Avenue, North Fremantle | 1897 | Witton's Directory |
| Cotton | E. W. | | Northam | 1897 | Witton's Directory |
| Cotton | James | Farmer | Wellington (Brunswick, Collie, Harvey, & Perth Road) | 1880 | WA Almanack |
| Cotton | James | Farmer | Wellington District (Brunswick, Collie, Harvey & Perth Road) | 1882 | WA Almanack |
| Cotton | James | Farmer | Wellington District (Brunswick Collie Harvey & Perth Road) | 1884 | WA Almanack |
| Cotton | James | Farmer | Wellington District (Brunswick, Collie, Harvey & Perth Road) | 1886 | WA Almanack |
| Cotton | James | Farmer | Brunswick, Collie, Harvey & Perth Road | 1887 | WA Almanack |
| Cotton | James | Farmer | Bunbury (Brunswick, Collie, Harvey & Perth Road) | 1888 | WA Almanack |
| Cotton | James | Farmer | Bunbury, Etc. (Brunswick, Collie, Harvey & Perth Road) | 1889 | WA Almanack |
| Cotton | James. | Farmer | Wellington District (Brunswick, Collie, Harvey, & Perth Road) | 1881 | WA Almanack |
