| I.O.O. | - | Cnr. William & James Street, Perth | Dodge | 2745 | Metro Private Car | 1925-26 |
| I.O.O. | - | Cnr. William & James Street, Perth | Dodge | 2745 | Metro Private Car | 1926-27 |
| I.O.O. | - | Cnr. William & James Street, Perth | Dodge | 2745 | Metro Private Car | 1927-28 |
| Ibbotson | C. A. | 121 Hay Street, Subiaco | Dealers | 20043 | Metro Dealers Car | 1924-25 |
| Ibbotson | C. H. | 121 Hay Street, Subiaco | Studebaker | 2509 | Metro Private Car | 1922-23 |
| Ibbotson | C. H. | 121 Hay Street, Subiaco | Studebaker | 2509 | Metro Private Car | 1923-24 |
| Ibbotson | C. H. | 121 Hay Street, Subiaco | Maxwell | 2509 | Metro Private Car | 1924-25 |
| Ibbotson | C. H. | 121 Hay Street, Subiaco | Maxwell | 2509 | Metro Private Car | 1925-26 |
| Ibbotson | C. H. | North Perth | Maxwell | 2509 | Metro Private Car | 1926-27 |
| Ibbotson | C. H. | 485 Fitzgerald Street, North Perth | Maxwell | 2509 | Metro Private Car | 1927-28 |
| Ich | F. H. | Albany | Durant | A 7 | Municipality of Albany | 1926-27 |
| Ick | F. H. | - | Ford 20 H.P. | NRB | Nelson Road Board | 1915 |
| Ick | F. H. | - | Ford 20 H.P. | NE 9 | Nelson Road Board | 1916 |
| Ick | F. H. | Bridgetown | Ford 20 H.P. | B ● 9 | Bridgetown Road Board | 1917-18 |
| Ick | F. H. | Bridgetown | Ford 20 H.P. | B ● 9 | Bridgetown Road Board | 1919 |
| Ick | F. H. | Stirling Terrace | Durant | A 7 | Albany Municipality | 1922-23 |
| Ick | F. H. | Albany | Durant | A 7 | Albany Municipality | 1923-24 |
| Ick | F. H. | Albany | Durant | A 7 | Municipality of Albany | 1924-25 |
| Ick | F. H. | Albany | Durant | A 7 | Municipality of Albany | 1925-26 |
| Ick | F. H. | Albany | Durana | A 7 | Albany Municipality | 1927-28 |
| Ickeringill | R. | Bullfinch | Reo Wagon | YL ● 8 | Yilgarn Road Board | 1925-26 |
| Ickeringill | R. | Bullfinch | Reo Truck | YL ● 2 | Yilgarn Road Board | 1926-27 |
| Ida | H. G. M. Co. | Ida H. | Ford 20 H.P. | MG 1 | Mount Margaret Road Board | 1916 |
| Ida Valley Station | - | Menzies | Dodge | MN ● 70 | Menzies Road Board | 1926-27 |
| Ida Valley Station | - | Menzies | Dodge | MN ● 70 | Menzies Road Board | 1927-28 |
| Iddam | - | Leonora | DeDion | LM ● 17 | Leonora-Malcolm Road Board | 1923-24 |
| Iddies | W. | 32 Bruce Street, Leederville | Ford | 8870 | Metro Private Car | 1925-26 |
| Iddon | G. | Collie | Austin | CM 203 | Collie Municipality | 1927-28 |
| Iddon | G. G. | Forrest Street, Collie | Dodge | CM 10 | Collie Municipality | 1925-26 |
| Iddon | G. G. | Throssell Street, Collie | Ford | CM 35 | Collie Municipality | 1925-26 |
| Iddon | G. G. | Throssell Street, Collie | Graham Truck | CM 94 | Collie Municipality | 1925-26 |
| Iddon | G. G. | Throssell Street, Collie | Ford | CM 35 | Collie Municipality | 1926-27 |
| Iddon | G. G. | Forrest Street, Collie | Graham Truck | CM 94 | Collie Municipality | 1926-27 |
| Iddon | G. G. | Forrest Street, Collie | Dodge | CM 146 | Collie Municipality | 1926-27 |
| Iddon | G. G. | Forrest Street, Collie | Dodge | CM 163 | Collie Municipality | 1926-27 |
| Iddon | G. G. | Forrest Street, Collie | Graham Truck | CM 94 | Collie Municipality | 1927-28 |
| Iddon | G. G. | Forrest Street, Collie | Dodge | CM 163 | Collie Municipality | 1927-28 |
| Iddon | George G. | Forrest Street | Dodge | CM ● 10 | Collie Municipality | 1922-23 |
| Iddon | George G. | Forrest Street | Dodge | CM 10 | Collie Municipality | 1923-24 |
| Iddon | George G. | Forrest Street, Collie | Dodge | CM 10 | Collie Municipality | 1924-25 |
| Ideal Motors | - | 822 Queen Victoria Street, Fremantle | Dealers | 20190 | Metro Dealers Car | 1926-27 |
| Ideal Motors | - | 822 Queen Victoria Street, Fremantle | Dealers | 20190 | Metro Dealers Car | 1927-28 |
| Ieman | E. S. | Booralaming | Ford | D ● 126 | Dowerin Road Board | 1925-26 |
| Iggo | Charles | 53 Temple Street, Victoria Park | Ford | 14694 | Metro Private Car | 1927-28 |
| Ihlan | H. | Nungarin | Pulman | NA ● 8 | Nullagine Road Board | 1922-23 |
| IIbery | T. H. | Mundaring | Chevrolet | GE ● 56 | Greenmount Road Board | 1925-26 |
| IIbery | T. H. | Mundaring | Chevrolet Truck | GE ● 37 | Greenmount Road Board | 1926-27 |
| IIbery | T. H. | Mundaring | Oakland | GE ● 5 | Greenmount Road Board | 1927-28 |
| IIbery | T. H. | Mundaring | Chevrolet Truck | GE ● 37 | Greenmount Road Board | 1927-28 |
| IIes | G. | Nangeenan | Oakland | MD ● 52 | Merredin Road Board | 1925-26 |