| Table ID No. | MCAG | Legal Name | Entity Name | Government Description |
| 1963 | 1895 | Oak Harbor School District No. 201 | Oak Harbor School District No 201 | School Districts |
| 393 | 0361 | City of Oak Harbor | Oak Harbor, City of | City/Town |
| 1596 | 0522 | Oakesdale Park and Recreation District No. 4 | Oakesdale Park and Recreation District No 4 | Park and Recreation District |
| 1964 | 2663 | Oakesdale School District No. 324 | Oakesdale School District No 324 | School Districts |
| 394 | 0816 | Town of Oakesdale | Oakesdale, Town of | City/Town |
| 1965 | 1894 | Oakville School District No. 400 | Oakville School District No 400 | School Districts |
| 395 | 0350 | City of Oakville | Oakville, City of | City/Town |
| 1966 | 1984 | Ocean Beach School District No. 101 | Ocean Beach School District No 101 | School Districts |
| 396 | 0352 | City of Ocean Shores | Ocean Shores, City of | City/Town |
| 1967 | 1893 | Ocosta School District No. 172 | Ocosta School District No 172 | School Districts |
| 1725 | 2769 | Odessa Public Development Authority | Odessa Public Development Authority | Public Development Authority |
| 1968 | 1963 | Odessa School District No. 105 | Odessa School District No 105 | School Districts |
| 397 | 0512 | Town of Odessa | Odessa, Town of | City/Town |
| 846 | 0763 | Office of Emergency Management | Office of Emergency Management | Emergency Management Services |
| 584 | 2741 | Okanogan Conservation District | Okanogan Conservation District | Conservation District |
| 639 | 0146 | Okanogan County | Okanogan County | County |
| 173 | 0053 | Okanogan County Cemetery District No. 1 | Okanogan County Cemetery District No 1 | Cemetery District |
| 174 | 0054 | Okanogan County Cemetery District No. 2 | Okanogan County Cemetery District No 2 | Cemetery District |
| 175 | 0055 | Okanogan County Cemetery District No. 3 | Okanogan County Cemetery District No 3 | Cemetery District |
| 176 | 0424 | Okanogan County Cemetery District No. 4 | Okanogan County Cemetery District No 4 | Cemetery District |
| 1058 | 1234 | Okanogan County Fire Protection District No. 1 | Okanogan County Fire Protection District No 1 | Fire Protection District |
| 1059 | 2555 | Okanogan County Fire Protection District No. 10 | Okanogan County Fire Protection District No 10 | Fire Protection District |
| 1060 | 0402 | Okanogan County Fire Protection District No. 11 | Okanogan County Fire Protection District No 11 | Fire Protection District |
| 1061 | 0691 | Okanogan County Fire Protection District No. 12 | Okanogan County Fire Protection District No 12 | Fire Protection District |
| 1062 | 1235 | Okanogan County Fire Protection District No. 2 | Okanogan County Fire Protection District No 2 | Fire Protection District |
| 1063 | 1236 | Okanogan County Fire Protection District No. 3 | Okanogan County Fire Protection District No 3 | Fire Protection District |
| 1064 | 1237 | Okanogan County Fire Protection District No. 4 | Okanogan County Fire Protection District No 4 | Fire Protection District |
| 1065 | 1238 | Okanogan County Fire Protection District No. 5 | Okanogan County Fire Protection District No 5 | Fire Protection District |
| 1066 | 1239 | Okanogan County Fire Protection District No. 6 | Okanogan County Fire Protection District No 6 | Fire Protection District |
| 1067 | 1240 | Okanogan County Fire Protection District No. 7 | Okanogan County Fire Protection District No 7 | Fire Protection District |
| 1068 | 1241 | Okanogan County Fire Protection District No. 8 | Okanogan County Fire Protection District No 8 | Fire Protection District |
| 1069 | 1242 | Okanogan County Fire Protection District No. 9 | Okanogan County Fire Protection District No 9 | Fire Protection District |
| 1361 | 1146 | Okanogan County Housing Authority | Okanogan County Housing Authority | Housing Authority |
| 811 | 0563 | Okanogan County Industrial Development Corporation | Okanogan County Industrial Development Corporation | Economic/Industrial Development |
| 1281 | 0599 | Okanogan County Public Health | Okanogan County Public Health | Health District |
| 1322 | 1482 | Okanogan County Public Hospital District No. 3 | Okanogan County Public Hospital District No 3 | Hospital District |
| 1323 | 1483 | Okanogan County Public Hospital District No. 4 | Okanogan County Public Hospital District No 4 | Hospital District |
| 1773 | 1792 | Public Utility District No. 1 of Okanogan County | Okanogan County Public Utility District No 1 | Public Utility District (PUD) |
| 2143 | 2811 | Okanogan County Water Conservation Board | Okanogan County Water Conservation Board | Water Conservation Board |
| 1458 | 1586 | Okanogan Irrigation District | Okanogan Irrigation District | Irrigation and Reclamation District |
| 1969 | 1977 | Okanogan School District No. 105 | Okanogan School District No 105 | School Districts |
| 2121 | 2371 | Okanogan Television Reception District No. 1 | Okanogan Television Reception District No 1 | TV Reception District |
| 2122 | 2372 | Okanogan Television Reception District No. 2 | Okanogan Television Reception District No 2 | TV Reception District |
| 398 | 0531 | City of Okanogan | Okanogan, City of | City/Town |
| 1324 | 1481 | Okanogan-Douglas County Hospital District No. 1 | Okanogan-Douglas County Hospital District No 1 | Hospital District |
| 2277 | 2284 | Old Bangor Water District | Old Bangor Water District | Water/Sewer District |
| 1970 | 2069 | Olympia School District No. 111 | Olympia School District No 111 | School Districts |
| 399 | 0751 | City of Olympia | Olympia, City of | City/Town |
| 1669 | 1761 | Port of Olympia | Olympia, Port of | Port District (Includes Airports) |
| 120 | 0275 | Olympic Area Agency on Aging | Olympic Area Agency on Aging | Area Agency on Aging |
| 547 | S662 | Olympic College | Olympic College | Community or Technical College |
| 828 | 2645 | Olympic Educational Service District No. 114 | Olympic Educational Service District No 114 | Educational Service District (ESD) |
| 111 | 1027 | Olympic Region Clean Air Agency | Olympic Region Clean Air Agency | Air Pollution District |
| 2278 | 2314 | Olympic View Water and Sewer District | Olympic View Water and Sewer District | Water/Sewer District |
| 2279 | 2177 | Olympus Terrace Sewer District | Olympus Terrace Sewer District | Water/Sewer District |
| 1971 | 1976 | Omak School District No. 19 | Omak School District No 19 | School Districts |
| 400 | 0533 | City of Omak | Omak, City of | City/Town |
| 1972 | 1956 | Onalaska School District No. 300 | Onalaska School District No 300 | School Districts |
| 1973 | 2054 | Onion Creek School District No. 30 | Onion Creek School District No 30 | School Districts |
| 1519 | 0611 | Orcas Island Library District | Orcas Island Library District | Library District |
| 1974 | 2011 | Orcas Island School District No. 137 | Orcas Island School District No 137 | School Districts |
| 1670 | 1755 | Port of Orcas | Orcas, Port of | Port District (Includes Airports) |
| 1459 | 1593 | Orchard Avenue Irrigation District No. 6 | Orchard Avenue Irrigation District No 6 | Irrigation and Reclamation District |
| 1460 | 1610 | Orchard Irrigation District No. 10 | Orchard Irrigation District No 10 | Irrigation and Reclamation District |
| 1975 | 2041 | Orchard Prairie School District No. 123 | Orchard Prairie School District No 123 | School Districts |
| 1976 | 1863 | Orient School District No. 65 | Orient School District No 65 | School Districts |
| 1977 | 1854 | Orondo School District No. 13 | Orondo School District No 13 | School Districts |
| 847 | 1112 | Oroville City Emergency Management Services | Oroville City Emergency Management Services | Emergency Management Services |
| 1362 | 1313 | Oroville Housing Authority | Oroville Housing Authority | Housing Authority |
| 848 | 1132 | Oroville Rural Emergency Management Service | Oroville Rural EMS | Emergency Management Services |
| 1978 | 1983 | Oroville School District No. 410 | Oroville School District No 410 | School Districts |
| 401 | 0535 | City of Oroville | Oroville, City of | City/Town |
| 1461 | 1587 | Oroville-Tonasket Irrigation District | Oroville-Tonasket Irrigation District | Irrigation and Reclamation District |
| 1979 | 2001 | Orting School District No. 344 | Orting School District No 344 | School Districts |
| 402 | 0594 | City of Orting | Orting, City of | City/Town |
| 585 | 2383 | Othello Conservation District | Othello Conservation District | Conservation District |
| 1363 | 1495 | City of Othello Housing Authority | Othello Housing Authority | Housing Authority |
| 1520 | 2785 | Othello Library District No.1 | Othello Library District No.1 | Library District |
| 1671 | 1696 | Othello Port District | Othello Port District | Port District (Includes Airports) |
| 1980 | 1810 | Othello School District No. 147 | Othello School District No 147 | School Districts |
| 403 | 0188 | City of Othello | Othello, City of | City/Town |
| 71 | S467 | Interagency Committee for Outdoor Recreation | Outdoor Recreation, Interagency Committee for | Agency, Commission, or Board |
