California - Criteria: C (architecture/engineering)
| Lincoln Park Historic District |
| Lincoln Public Library |
| Lindstrom House |
| Lisbon Winery |
| Little Tokyo Historic District |
| Livermore Carnegie Library and Park |
| Llano Road Roadhouse |
| Lloyd, Harold, Estate |
| Locke Historic District |
| Locke House |
| Locke's Meat Market |
| Lodi Arch |
| Loewy House |
| Lompoc Public Library |
| Long Beach Professional Building |
| Longfellow-Hastings House |
| Longley, Howard, House |
| Long-Waterman House |
| Lopez Adobe |
| Loring House |
| Los Alamos Ranch House |
| Los Altos Apartments |
| Los Angeles Central Library |
| Los Angeles Pacific Company Ivy Park Substation |
| Los Angeles Plaza Historic District |
| Los Angeles Union Passenger Terminal |
| Los Banos del Mar |
| Los Cerritos Ranch House |
| Los Gatos Historic Commercial District |
| Los Rios Street Historic District |
| Lotta Crabtree Fountain |
| Louie's Place |
| Lovejoy Homestead |
| Lovell Beach House |
| Lovell House |
| Lower Arroyo Seco Historic District |
| Lower Blackburn Grade Bridge |
| Lower Nob Hill Apartment Hotel District |
| Lukens, Theodore Parker, House |
| Lummis House |
| Lumsden, W. H., House |
| Lyford, Benjamin and Hilarita, House |
| Lyford's Stone Tower |
| Lynwood Pacific Electric Railway Depot |
| Lyons Ranches Historic District |
| Machell-Seaman House |
| Madera County Courthouse |
| Madison House |
| Madison Park Apartments |
| Madrona Knoll Rancho District |
| Main Building |
| Main Post Office and Federal Building |
| Main Street Historic District-Winters |
| Malabar Branch |
| Malakoff Diggins-North Bloomfield Historic District |
| Maloof, Sam and Alfreda, Compound |
| Manasse Mansion |
| Manchester Schoolhouse |
| Mansion House Hotel |
| Manzanita Lake Naturalist's Services Historic District |
| March Field Historic District |
| Marconi-RCA Bolinas Transmitting Station |
| Marengo Gardens |
| Marentis House |
| Marin County Civic Center |
| Marine Corps Recruit Depot Historic District |
| Marinship Machine Shop |
| Mariona |
| Mariposa County Courthouse |
| Mariposa Grove Museum |
| Marsh, G.T., and Sons |
| Marsh, John, House |
| Marsh, Martin Luther, House |
| Marston, George W., House |
| Martinez Canyon Rockhouse |
| Martinez City Library |
| Martinez Downtown Post Office |
| Martinez Grammar School Annex |
| Martin, Samuel, House |
| Mary Louise Court |
| Masonic Temple |
| Masonic Temple |
| Masonic Temple and Lodge |
| Masonic Temple-Naval Lodge No. 87, Free and Accepted Masons |
| Masson, Paul, Mountain Winery |
| Matson Building and Annex |
| Maulbridge Apartments |
| Maxfield Building |
| Maxwell Creek Bridge on Hardin Road |
| Maydestone Apartments |
| Mayfair Hotel |
| McCallum, Roy D., House |
| McCarty Memorial Christian Church |
| McCauley and Meyer Barns |
| McCauley Cabin |
| McClatchy, C.K., Senior High School |
| McClintock Storage Warehouse |
| McCloud |
| McCrea House |
| McCrea, Joel, Ranch |
Data from United States Park Service and Wikidata
