| Hyder Bros. | - | Tamara, Boyanup | 5IY and 11B, 40E | 1962 |
| Hydre | L. | Browers Creek, Mt. Malcolm | L5K | 1924 |
| Hyland | G. M. | Dongolocking Park, Wagin East | H7G | 1912 |
| Hyland | G. M. | Dongolocking Park, Wagin | H7G | 1924 |
| Hymus | George F. | Sunny Vale, P. O. Wyalkatchem | 4GH | 1927 |
| Hymus | Grace E. | Camballing, Marradong | GE2 | 1912 |
| Hymus | Grace E. | Camballing, Marradong | GE2 | 1924 |
| Hynam | Chas. | Hynam's Farm, Bruce Rock | 5KY | 1924 |
| Hyne | C. R. | Yappara, Guildford | 6CH | 1912 |
| Hyne | C. R. | Yappara, Guildford | 6CH | 1924 |
| Hyne | J .V. & C. M. | Swan Loc. 1875, 2781, South Guildford | 6CH and 102C, 84E | 1962 |
| Hyne | R. R. | Loc. 5A, Lot 25, Lot 1352, Lot 1921, Upper Swan Muchea | 6RH and 44A, 49 B | 1962 |
| Hynes | B. R. & M. G. | Yenagin, East Pingelly | B7H and 44D, 7E | 1962 |
| Hynes | C. T. | Avonlea Loc. 669 Lot 4, Waterloo | 7DJ and 30D, 15E | 1962 |
| Hynes | E. | Karaim, Calingiri | 6NH | 1924 |
| Hynes | J. J. | Fir Park, Waterloo | O7C and 51F, 41D | 1962 |
| Hynes | J. J. | Erinore, Hyden | P0Y and 22B, 119E | 1962 |
| Hynes | J. J. | Erinore, Hyden | RD3 and 42D, 29E | 1962 |
| Hynes | L. A. | Loc. 669, Lot1, Waterloo | 7H9 and 19D, 53F | 1962 |
| Hyslop & Waugh | - | Hootanni G.M., Mulga Queen | 4HW | 1912 |
| I'Anson | D. L. & M. J. | Greenwood, Darkan | MA1 and 16C, 6A | 1962 |
| Ibbotson | Reginald J. | Lyndhurst, 5th Street, Harvey | RM1 | 1927 |
| Ibbotson & Smith Bros. | - | Mooloogore, via Meekatharra | SX1 | 1924 |
| Ibbs | G. | Chandala, Muchea | 1WU and 113A, 11B | 1962 |
| Ibister & Pfitzner | - | Pt. Zongala, Morawa | E0P and 45E, 41D | 1962 |
| Ibister & Sons | J. | Homewood, Moora | 1BZ and 22C, 45,A | 1962 |
| Ickeringill | Thos. S. | Crown Lands, Bullfinch | 7KS | 1924 |
| Ieraci Bros. | - | Coolup No. A.A. lots 235-2-4, 255-6, Harvey, Wellington Loc. 653, 4087, 3530, Coolup and Harvey | RT6 and 118A, 116B | 1962 |
| Ietto | D. | Loc. 183, Harvey | D8G and 116D, 44E | 1962 |
| Iffla | A. S. | 5949, 5952, SOuth Stirling via Mt. Barker | QK1 and 17C, 42E | 1962 |
| Iffla | Anne Eliz. | Nelson Loc. 4043, Nannup | F5O | 1924 |
| Iffla | Harold A. | Yellanup, Porongorup Mail, via Mt. Barker | QK1 | 1924 |
| Iffla & Millar | H. A. H. & A. | Ahgl Dere, Iffley, via Nannup | FF9 | 1924 |
| Ignotti | A. | Bellview, Loc. 3857, Witchcliffe | AB3 | 1962 |
| Ilbery | W. S. | Quanaminning, Wogolin Road, East Wickepin | WQ1 | 1924 |
| Iles | F. J. | Scarborough Farm, Cumminin | 4LE | 1912 |
| Iles | F. J. | Scarborough Farm, Kumminin | 4LE | 1924 |
| Iles | Felix Wm. | Olivia Terrace, Carnarvon | F8V | 1924 |
| Iles | Francis Herbert | East Kumminin, via Bruce Rock | F7V | 1924 |
| Iles | G. A. & H. D. | 27183 Sussex Loc, Margaret River | TN9 and 110D, 84E | 1962 |
| Iles | Geo. | Block 15592, Nangeenan | 7GN | 1912 |
| Iles | Geo. | Block 15592, Nangeenan | 7GN | 1924 |
| Iles | John E. | Sunnyside Farm, Carnamah | XE8 | 1924 |
| Iles | John W. | Emu Hill | J7X | 1924 |
| Iles | R. G. L. | Ella-Valla, Canarvon | RG2 and 5B, 26E | 1962 |
| Iles | Robt. Geo. L. | Commonage, Carnarvon | RG2 | 1924 |
| Iles | T. C. | Avon Loc. 15872, East Kuminin | TN9 | 1924 |
| Iles | Thos. | Hope Farm, Northern Gully | OT1 | 1912 |
| Iles | Thos. | Hope Farm, Northern Gully | OT1 | 1924 |
| Iles | W. J. | 26, Dardanup | G8J | 1962 |
