| Osborn | H. | Bruce Rock | Dodge | BK ● 169 | Bruce Rock Road Board | 1926-27 |
| Osborn | H. | Bruce Rock | Dodge | BK ● 169 | Bruce Rock Road Board | 1927-28 |
| Osborn | J. | Bruce Rock | Indian 7-9 H.P. | BR ● 2 | Bruce Rock Road Board | 1919 |
| Osborn | L. H. | Bruce Rock | Ford | BK ● 268 | Bruce Rock Road Board | 1927-28 |
| Osborn | S. | Guildford | Argyle 20 H.P. | MJ 33 | Midland Junction Municipality | 1916 |
| Osborne | A. | Allanson | Cleveland | CO ● 121 | Collie Road Board | 1926-27 |
| Osborne | A. J. | 55 Fremantle Road, Victoria Park | Overland | 5755 | Metro Private Car | 1926-27 |
| Osborne | A. J. | 55 Fremantle Road, Victoria Park | Overland | 5755 | Metro Private Car | 1927-28 |
| Osborne | D. K. | Fremantle Road, Gosnells | Fiat | 9252 | Metro Private Car | 1927-28 |
| Osborne | E. C. | Nedlands Park | Car | CL ● 23 | Claremont Road Board | 1917-18 |
| Osborne | E. C. | Nedlands Park | - | CL ● 23 | Claremont Road Board | 1919 |
| Osborne | G. W. | Meekatharra | Dodge 18-20 H.P. | MK 4 | Meekatharra Roads Borad | 1916 |
| Osborne | H. W. | Mortigalup | Overland Van | PL ● 137 | Plantagenet Road Board | 1927-28 |
| Osborne | L. V. | Mortigalup | Overland Truck | PL ● 109 | Plantagenet Road Board | 1927-28 |
| Osborne | M. H. | Bunbury | Chevrolet | BY 180 | Bunbury Municipality | 1927-28 |
| Osborne | N. | Darkan | Commerce Truck | AW ● 92 | West Arthur Road Board | 1927-28 |
| Osborne | S. | Merredin | Essex | MD ● 219 | Merredin Road Board | 1926-27 |
| Osborne | S. | Merredin | Essex | MD ● 219 | Merredin Road Board | 1927-28 |
| Osborne | T. | - | Chevrolet | CU ● 106 | Upper Chapman Road Board | 1926-27 |
| Osborne | T. | - | Chevrolet | CU ● 106 | Upper Chapman Road Board | 1927-28 |
| Osborne | W. H. | Bruce Rock | Essex for Trade or Hire | BK ● 11 | Bruce Rock Road Board | 1922-23 |
| Osborne | W. H. | Bruce Rock | Essex | BK ● 11 | Bruce Rock Road Board | 1924-25 |
| Osborne | W. H. | Bruce Rock | Buick | BK ● 172 | Bruce Rock Road Board | 1924-25 |
| Osborne | W. H. | Bruce Rock | Jewett | BK ● 11 | Bruce Rock Road Board | 1925-26 |
| Osborne | W. H. | Bruce Rock | Jewett | BK ● 11 | Bruce Rock Road Board | 1926-27 |
| Osborne | W. H. | Bruce Rock | Jewett | BK ● 11 | Bruce Rock Road Board | 1927-28 |
| Osborne | W. O. | Albany Road | Flanders 20 H.P. | VP 7 | Victoria Park Municipality | 1915 |
| Osborne | W. O. | Albany Road | Flanders 20 H.P. | VP 7 | Victoria Park Municipality | 1916 |
| Osborne | W. O. | 168 Albany Road, Victoria park | Chevrolet | 4413 | Metro Private Car | 1923-24 |
| Osborne | W. O. | 300 Albany Road, Victoria Park | Chevrolet | 4413 | Metro Private Car | 1925-26 |
| Osborne | W. O. | 300 Albany Road, Victoria Park | Chevrolet | 4413 | Metro Private Car | 1926-27 |
| Osborne | W. O. | 300 Albany Road, Victoria Park | Chevrolet | 4413 | Metro Private Car | 1927-28 |
| Osborne Co | S. P. | Goodrich Tyre Co | Essex | 965 | Metro Private Car | 1926-27 |
| Osbourne | A. | Allanson | Cleveland | CO ● 121 | Collie Road Board | 1927-28 |
| Osbourne | E. C. | 18 Kershaw Street, Subiaco | Studebaker | 1232 | Metro Private Car | 1922-23 |
| Osbourne | J. | Bruce Rock | Dodge | BK ● 16 | Bruce Rock Road Board | 1922-23 |
| Osbourne | S. P. | Jubilee Street, South Perth | Ford | 7823 | Metro Private Car | 1925-26 |
| Osbourne | Stanley P. | 41 Clifton Crescent, Mount Lawley | Essex | 965 | Metro Private Car | 1927-28 |
| Osbourne | W. H. | Bruce Rock | Essex | BK 11 | Bruce Rock Road Board | 1923 - 1924 |
| Osbourne | W. O. | Albany Road, Victoria Park | Flanders 20 H.P. | P 1084 | Perth Municipality | 1917-18 |
| Osbourne | W. O. | 300 Albany Road, Victoria Park | Chevrolet | 4413 | Metro Private Car | 1924-25 |
| Osbourne | Wm. O. | 168 Albany Road, Victoria Park | Flanders | 1377 | Metro Private Car | 1922-23 |
| Osterberg & Campbell | - | Trayning | Ford Truck | KTY ● 25 | Kununoppin-Trayning Road Board | 1927-28 |
| Ostle | T. | Wanneroo | Rugby | WN ● 29 | Wanneroo Road Board | 1926-27 |
| Ostle | T. | Wanneroo | Rugby | WN ● 29 | Wanneroo Road Board | 1927-28 |
| Oterberg & Campbell | - | 30 Collie Street, Fremantle | Ford Truck | 3982 | Metro Hire or Trade | 1926-27 |
| Otfer | M. G. | Colin Street, West Perth | Nash | 5031 | Metro Private Car | 1927-28 |
| OToole | M. J. | 168 Hay Street | Car | S 44 | Subiaco Municipality | 1917-18 |
| Ottaway | A. E. | Wyalkatchem | Chrysler | WM ● 188 | Wyalkatchem Road Board | 1926-27 |
| Ottaway | A. E. | Wyalkatchem | Chrysler | WM ● 188 | Wyalkatchem Road Board | 1927-28 |
