Washington - Criteria: C (architecture/engineering)
| Kiggins, John P. and Mary, House |
| Kiggins Theater |
| Kirk, Lilly, House |
| Kirkman House |
| Knickerbocker |
| Kristoferson Dairy |
| Krumdiack Homestead |
| Lake George Patrol Cabin |
| Lake Quinault Lodge |
| Lake Washington Boulevard |
| LA MERCED |
| Larrabee House |
| Larson, A. E., Building |
| Laughlin Round Barn |
| La Wis Wis Guard Station No. 1165 |
| Leary, Eliza Ferry, House |
| Leavenworth Ranger Station |
| Leavenworth Ski Hill Historic District |
| Lester Depot |
| Lewis & Clark High School |
| Lewis County Courthouse |
| Lewisville Park |
| Liberty Theater |
| Liggett Building |
| Little Falls Hydroelectric Power Plant |
| Long Lake Hydroelectric Power Plant |
| Longmire Buildings |
| Longmire Campground Comfort Station No. L-302 |
| Longmire Campground Comfort Station No. L-303 |
| Longmire Campground Comfort Station No. L-304 |
| Longmire Historic District |
| Long, Robert Alexander, High School |
| Longview Bridge |
| Longview Community Church |
| Longview Community Church-Saint Helen's Addition |
| Longview Women's Clubhouse |
| Lost Lake Guard Station |
| LOTUS (motor vessel) |
| Lumber Exchange Building |
| Lutheran St. Paul's Kirche |
| Lyon Building |
| Lytle, Joseph, Home |
| Manito Park and Boulevard |
| Manning-Rye Covered Bridge |
| Marcus Whitman Hotel |
| Marycliff-Cliff Park Historic District |
| Maryhill |
| Mary Queen of Heaven Roman Catholic Church |
| Marysville Opera House |
| Masonic Hall |
| Masonic Temple |
| Masonic Temple |
| Masonic Temple-Auburn |
| Masonic Temple Building-Temple Theater |
| Masonic Temple-Hoquiam |
| McAlmond House |
| McCabe Building |
| McChord Field Historic District |
| McFadden, O. B., House |
| McMillin Bridge |
| Medical Dental Building |
| Meeker, Ezra, Mansion |
| Meese, Gustav, Building |
| Methodist Epscopal Church of Port Hadlock |
| Michael's Cabin |
| Miller Block |
| Miller, George, House |
| Millersylvania State Park |
| Mills Building |
| Millwood Historic District |
| Miners Ridge Lookout |
| Monroe Street Bridge |
| Monte Cristo Hotel |
| Montlake Bridge |
| Montlake Historic District |
| Montvale Block |
| Moore Theatre and Hotel |
| Moran State Park |
| Mount Baker Ridge Tunnel |
| Mount Baker Theatre |
| Mount Rainier National Park |
| Mount Saint Michael |
| Mount Spokane Vista House |
| Mowich Lake Patrol Cabin |
| Mt. Fremont Fire Lookout |
| Mukai Cold Process Fruit Barrelling Plant |
| Mukilteo Light Station |
| MV KALAKALA (ferry) |
| MV PLOVER (ferry) |
| MV WESTWARD (Wooden Motor Vessel) |
| Narada Falls Bridge |
| Narada Falls Comfort Station |
| National Bank of Tacoma |
| Naval Air Station (NAS) Seattle |
| Naval Lodge Elks Building |
| Naval Military Hangar-University Shell House |
| Naval Reserve Armory |
| Neely, Sr., Aaron and Sarah, Farm |
| Nettleton's Addition Historic District |
| Nifty Theatre |
Data from United States Park Service and Wikidata
