| Koonmarra Pastoral Co. | - | Koonmarra, Box 5 Meekatharra | UG0 | 1927 |
| Koonmarra Pastoral Co. | - | Koonmarra, Meekatharra | H0S and 4A, 33C | 1962 |
| Koorian Estate | - | Koorian, Gingin | 3HK and 25A, 2C | 1962 |
| Kooshal | - | Commonage, Port Hedland | K3L | 1912 |
| Kooshal | - | Commenage, Port Hedland | K3L | 1924 |
| Kooyong Pastoral Co. | | Koyong, Tenindewa | KP4 and 84C, 31A | 1962 |
| Kopec | J. | Sussex Loc. 3640, Rosa Glen, via Margaret River | K2K | 1962 |
| Kopke | F. A. H. | Yaringa, Wooramel, Via Carnarvon | DH2 | 1924 |
| Kopke | N. E. & M. J. | Yaringa North Station, Carnarvon | DH2 and 33B, 22E | 1962 |
| Korn & Co. | R. B. | Wood Falls, Boyup Brook | 1RK and 19A, 21C | 1962 |
| Korn & Son | G. W. | Forrard Away, Boyup Brook | 4KB and 3B, 39E | 1962 |
| Koseritz | Hans | Strawberry Farm, Mundaring | 2KB | 1912 |
| Koseritz | Hans | Strawberry Farm, Mundaring | 2KB | 1924 |
| Kosick | A. C. | Swan Lot 98, Midland Junction | 5AK and 3D, 27E | 1962 |
| Kosick Bros. | (M. & N. F.) | Swan Loc. 1317, Midland Junction | 7NK | 1962 |
| Kosonen | P. J. | Loc. 1655, Dingup, via Manjimup | OKN and 114B, 110E | 1962 |
| Kosta | G. | Allendale, Williams | 5GK and 67E, 9D | 1962 |
| Kostanich | Nicholas | Commonage, Meekatharra | X7K | 1924 |
| Koster | Johana L. | Hollandia, Pemberton | LK9 | 1927 |
| Koster | W. | Pleasant View, Ryans Brook, via Kojonup | 1WK and 80D, 18E | 1962 |
| Kotsicos | M. | Dundangin Farm, Mukinbudin | M2K and 34D, 120E | 1962 |
| Kowald | A. W. | The Grange Riverdale and Highlands, Katanning | WK8 and 5B, 17E | 1962 |
| Kowald | C. R. | Crystal Brook and Loc. 7089, Katanning and Beaufort River | C7K and 52F, 84B | 1962 |
| Kowald | E. L. | Sunny View, Katanning | K1E and 10A, 20B | 1962 |
| Kowald | E. P. | Block No. 355-6, 1729, 1742, Katanning | EK2 and 14B, 26E | 1962 |
| Kowald | F. E. | Kooringa, Katanning | 7CL and 80C, 10A | 1962 |
| Kowald | F. O. | Homeside, Katanning | F0K and 47E, 29D | 1962 |
| Kowald | Fred W. | The Grange, Katanning | WK8 | 1912 |
| Kowald | Fred W. | The Grange, Katanning | WK8 | 1924 |
| Kowald | G. O. | Mugga Wagga, Victoria Loc. 7141, 7476, 7140, 1527, 8941, 8129, 8128, Canna | G9K and 112D, 15E | 1962 |
| Kowald | G. W. R. | Malvern Hill, Katanning | K0R | 1912 |
| Kowald | G. W. R. | Malvan Hill, Katanning | K0R | 1924 |
| Kowald | G. W. R. | Malvern Hill, Katanning | K0R and 41B, 48A | 1962 |
| Kowald | H. A. | Eulymartup Farm, Katanning | 3KA | 1924 |
| Kowald | H. A. | H.F. 16949/74, Katanning | LK8 | 1924 |
| Kowald | I. L. | Williams Loc. 995, 996, 998, Pt. 45, 12301, 3, 27, 770, Katanning | 0LK and 12E, 47B | 1962 |
| Kowald | L. W. | Woodlands, Katanning | LK1 and 48A, 18B | 1962 |
| Kowald | M. R. | Birdwood, Cheery Tree Pool | M1K and 107A, 36B | 1962 |
| Kowald | N. E. | Capemont, Katanning | N4K and 50C, 108E | 1962 |
| Kowald | R. J. | Pindawa, Canna | JK7 and 7A, 33C | 1962 |
| Kowald | R. P. | Jam Hills, Katanning | 3PK and 10B, 45E | 1962 |
| Krakouer | Alfred | Ryan's Brook, Cranbrook | A6K | 1924 |
| Krakouer | D. | Water Dale, Kojonup | DK2 | 1912 |
| Krakouer | D. | Water Dale, Kojonup | DK2 | 1924 |
| Krakouer | Raphael | Kojonup, Kojonup | RK2 | 1912 |
| Krakouer | Raphael | Kojonup | EK8 | 1924 |
| Kramer | E. H. | Merkanooka, Via Mingenew | EK8 | 1924 |
| Kramer | H. W. | Oak-bank, Wagin | 1HK | 1912 |
| Kramer | H. W. | Oakbank, Wagin | 1HK | 1924 |
| Krapljanov | B. | Nelson 866, Bridgetown | 9BK and 21B, 117E | 1962 |
