California - Area of significance: Architecture
| Los Gatos Historic Commercial District |
| Los Rios Street Historic District |
| 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 |
| Lyon, W. Parker, House |
| Machell-Seaman House |
| Madera County Courthouse |
| Madison House |
| Madison Park Apartments |
| Madrona Knoll Rancho District |
| Madulce Guard Station and Site |
| Main Building |
| Main Post Office and Federal Building |
| Main Street Historic District-Winters |
| Malabar Branch |
| Malaga Cove Plaza |
| 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 |
| Marconi Wireless-Synanon Tomales Bay Headquarters Historic District |
| Marengo Gardens |
| Marentis House |
| Marguerita Lane Historic District |
| Marin Art and Garden Center |
| Marin City Public Housing |
| Marin County Civic Center |
| Marine Corps Recruit Depot Historic District |
| Mariona |
| Mariposa County Courthouse |
| Mariposa County High School Auditorium |
| Mariposa Grove Museum |
| Mariposa Town Historic District |
| Market Street Theatre and Loft District |
| Markham Place Historic District |
| 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 |
| Martinez Historical District |
| 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 |
| Mathews, Arthur C. and Judith, House |
| Matson Building and Annex |
| Maulbridge Apartments |
| Maxfield Building |
| 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 |
| McCullagh-Jones House |
| McDonald, D. C., Building |
| McDonald Mansion |
| McElroy Octagon House |
| McFarlan, George, House |
| McHenry Mansion |
| McMullen, John, House |
| McNally's Windemere Ranch Headquarters |
| McNear, Erskine, B., House |
| Medico-Dental Building |
| Meek Mansion and Carriage House |
| Mello, Clarence and Mary, House |
| Melrose-Backs Neighborhood Houses |
| Melrose Baptist Church |
| Memorial Branch |
| Memorial Hall |
| Mendocino and Headlands Historic District |
| Mendocino Woodlands Recreational Demonstration Area |
Data from United States Park Service and Wikidata
