| Kopke | F. A. | 304 Fitzgerald Street | Overland 25 H.P. | P 198 | Perth Municipality | 1919 |
| Kopke | F. A. | 66 Lawley Crescent, Mount Lawley | Willy's-Knight | 390 | Metro Private Car | 1923-24 |
| Kopke | F. A. | 66 Lawley Crescent, Mount Lawley | Willys-Knight | 390 | Metro Private Car | 1925-26 |
| Kopke | F. A. | 66 Lawley Crescent, Mount Lawley | Willys-Knight | 390 | Metro Private Car | 1926-27 |
| Kopke | F. A. | 66 Lawley Crescent, Mount Lawley | Willys-Knight | 390 | Metro Private Car | 1926-27 |
| Kopke | Fred A. | 65 Lawley Crescent, Mount Lawley | Willys-Knight | 390 | Metro Private Car | 1922-23 |
| Kornbeibel | Albert | Wellington Street, Cottesloe Beach | Chevrolet | 2830 | Metro Private Car | 1927-28 |
| Korner | R. C. | 32 Charles Street, South Perth | Chevrolet | 12823 | Metro Private Car | 1927-28 |
| Korrelocking Co-op. | - | Korrelocking | Essex | WM ● 88 | Wyalkatchem Road Board | 1924-25 |
| Korrelocking Co-op. | - | Korrelocking | Essex | WM ● 88 | Wyalkatchem Road Board | 1925-26 |
| Korrelocking Co-op. | - | Korrelocking | Essex | WM ● 88 | Wyalkatchem Road Board | 1926-27 |
| Korsunski | Geo. | 197 Lake Street, Perth | Gray Wagon | 9419 | Metro Private Car | 1927-28 |
| Korunski | G. | 197 Lake Street, Perth | Overland | 8703 | Metro Private Car | 1926-27 |
| Korunski | G. | 197 Lake Street, Perth | Gray Wagon | 9419 | Metro Private Car | 1926-27 |
| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1925-26 |
| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1926-27 |
| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1927-28 |
| Koser | R. | 162 Brisbane Street, Perth | Harley Davidson & Sidecar | 974 | Metro Motorcycle | 1922-23 |
| Koster Webster | - | Kalamunda | Reo Bus | DR ● 59 | Darling Range Road Board | 1927-28 |
| Kostera & Webster | - | Kalamunda | Austin | DR ● 7 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Studebaker | DR ● 8 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Reo Bus | DR ● 24 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Federal Bus | DR ● 32 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Federal Bus | DR ● 59 | Darling Range Road Board | 1926-27 |
| Kostera and Webster | - | Kalamunda | Austin | DR ● 7 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Kalamunda | Studebaker | DR ● 8 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Kalamunda | Reo Bus | DR ● 24 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Maida Vale | Federal Bus | DR ● 32 | Darling Range Road Board | 1927-28 |
| Kosterich | F. B. | Ballidu | Ford Truck | WB ● 164 | Wongan-Ballidu Road Board | 1927-28 |
| Kosterick | J. | 537 Wellington Street, Perth | Overland | 7294 | Metro Private Car | 1925-26 |
| Kostos | George | 198 William Street, Perth | Chevrolet Wagon | 2970 | Metro Private Car | 1927-28 |
| Kott | M. | C.T.A. Chambers, Perth | Bean | 684 | Metro Private Car | 1922-23 |
| Kott | M. | C.T.A. Chambers, Perth | Bean | 684 | Metro Private Car | 1923-24 |
| Kott | M. | 56 Victoria avenue, Claremont | Hudson | 9923 | Metro Private Car | 1926-27 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Overland | 4665 | Metro Private Car | 1923-24 |
| Kott | Max | 692 Beanfort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1924-25 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1925-26 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1926-27 |
| Kott | Max | 50 Victoria Avenue, Claremont | Oakland | 7933 | Metro Private Car | 1927-28 |
| Kott | Max | 66 Victoria Avenue, Claremont | Chrysler | 670 | Metro Private Car | 1927-28 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Toad Board | 1922-23 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1923-24 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1924-25 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1925-26 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1926-27 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1927-28 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1925-26 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1926-27 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1927-28 |
| Kowald | G. W. R. | Katanning | Ford | KA ● 215 | Katanning Road Board | 1925-26 |