| Thornalley & Barnard | - | Jelkaline Est., Brookton | U1A | 1924 |
| Thorne | H. J | Commonage, Menzies | HT8 | 1912 |
| Thorne | H. J. | Commonage, Menzies | HT8 | 1924 |
| Thorne | H. S. | Plantagenet 2095, Denmark | YS2 | 1962 |
| Thorne | Henry | Loc. 568, Canning Mills | 5XT | 1924 |
| Thorne | James | Balla Balla, Mining Lease 137, Whim Creek | Z2T | 1924 |
| Thorne | W. J. | Thomleigh, Babakine, Doodlakine | 4WT | 1912 |
| Thorne | W. J. | Thomleigh, Babakine, Doodlakine | 4WT | 1924 |
| Thorne & Hunton | - | A7, Lower Kalgan, via Albany | 9TH and 120D, 18E | 1962 |
| Thornett | C. G. | M.331, Yandanooka | 7CG | 1962 |
| Thornett | C. G. | Coonaroo, Mt. Helena | CT1 and 8B, 38A | 1962 |
| Thornett | Ernest Edwd. | Wimmera Farm, Dowerin | 9TX | 1924 |
| Thornett | L. A. C. | Loc. 765, Denmark | 5LT | 1924 |
| Thornett | Richard | Maydale, Denmark | R3T | 1912 |
| Thornett | Richard | Maydale, Denmark | R3T | 1924 |
| Thornett & Chiplin | - | Ayanup Farm, via Kojonup | P2E | 1924 |
| Thornett & Son | J. & M. | Fraser Downs, Tenroth, Dowerin | H6O and 33B, 47E | 1962 |
| Thornett & Sons | E. T. | Coolerup, Kojonup | ZY0 | 1912 |
| Thornett & Sons | E. T. | Coolerup, Kojonup | ZY0 | 1924 |
| Thornley | H. S. | Causeway Farm, Narrogin | TX2 | 1924 |
| Thornley | Henry | The Dale, Clearlands, Beverley | HT1 | 1912 |
| Thornley | Henry | The Dale, Clearlands, Beverley | HT1 | 1924 |
| Thornlie Grazing Co. | - | Thornlie, Kenwick | TL1 and 24D, 12E | 1962 |
| Thornston | Fred | Oakleigh, Kojonup | F6T | 1926 |
| Thornton | D. C. | Kojonup 6273, 6796, 9021, Gnowangerup | D9T and 108B, 111E | 1962 |
| Thornton | E. | Byfield, Yallingup | ET6 | 1912 |
| Thornton | E. | Byfield, Yallinup | ET6 | 1924 |
| Thornton | E. J. | The Cliffs, Lake Grace | E9J and 45D, 24E | 1962 |
| Thornton | F. G. & F. | 275 Bateman Estate, Mundijong | FT2 | 1962 |
| Thornton | F. T. | Holmhurst, Broomehill | F6T and 19C, 28A | 1962 |
| Thornton | I. J. & A. J. | Kojonup 2220, 2672, 3476, 4738, Plantagenet 691, 1370, 2776, 2902, Port 1387, Gnowangerup | 9TJ and 11B, 117E | 1962 |
| Thornton | J. | Brookfields, Lake Grace | 0XB and 105B, 52F | 1962 |
| Thornton | J. | Beetaloo, Lake Grace | YU4 and 22B, 6A | 1962 |
| Thornton | James | Homestead, Brookton | 0JT | 1912 |
| Thornton | Jas. | Homestead, Brookton | 0JT | 1924 |
| Thornton | Mrs F. M. | Ambleside Farm and Castle Hills, Denmark | MT8 | 1924 |
| Thornton | Mrs. F. M. | Ambleside Farm and Castle Hills, Denmark | MT8 | 1912 |
| Thornton | S. L. | Golden Valley Farm, Wagin East | L9T | 1924 |
| Thornton | W. J. | Clydebank, Wagin East | QF2 | 1924 |
| Thornton | Wm. Harold | Shirley Farm, Kellerberrin | 7WT | 1912 |
| Thornton | Wm. Harold | Shirley Farm, Kellerberrin | 7WT | 1924 |
| Thornton- Smith & Sons | - | Wirrabara, Tammin | V3T and 48D, 31E | 1962 |
| Thorp | Albert Hy. | Albany Road, Maddington | XT5 | 1924 |
| Thorp | Frank Harris | Vict. Loc. 7014, Perenjori | U3X | 1924 |
| Thorpe | A. & A. | Coolibah, Bencubbin | F3G and 38D, 22E | 1962 |
| Thorpe | Ada | Loc. 353, Rockingham | X7T | 1924 |
| Thorpe | C. A. | 5215 Plantagenet, Narrikup | C2T and 21C, 103A | 1962 |
| Thorpe | E. & J. | Industrious Farm, Loc. 442, Rockingham | EJ0 | 1912 |
| Thorpe | E. & J. | Industrious Farm, Loc. 442, Rockingham | EJ0 | 1924 |
| Thorpe | E. C. | Wandoo Hills, Kojonup | 4ET and 3B, 16A | 1962 |
