California - Criteria: C (architecture/engineering)
| Poppy Peak Historic District |
| Portal of the Folded Wings Shrine to Aviation and Museum |
| Port Costa School |
| Porter Building |
| Porter-French House |
| Porter-Vallejo Mansion |
| Portola Valley School |
| Portuguese Chapel of San Diego |
| Post, George B., House |
| Post, Joseph W., House |
| Powerhouse, The |
| Pratt, Charles M., House |
| Presidio |
| Preston Castle |
| Price, John, House |
| Princeton Hotel |
| Professorville Historic District |
| Prospect Historic District |
| Pumping Station No. 2 San Francisco Fire Department Auxiliary Water Supply System |
| Pythian Castle |
| Pythias Lodge Building |
| Quarters 1, Yerba Buena Island, Naval Training Station |
| Queen Anne Cottage and Coach Barn |
| Radar Station B-71 |
| Railroad Square District |
| Rains, John, House |
| RALPH J. SCOTT |
| Ralphs Grocery Store |
| Ramirez, Jose Manuel, House |
| Ramona Street Architectural District |
| Ramsay-Durfee Estate |
| Rancho Camulos |
| Rancho El Encino |
| Rancho Guajome Adobe |
| Rancho Las Palmas |
| Rancho Los Alamitos |
| Rancho Olompali |
| Rancho Santa Fe Land and Improvement Company Office |
| Rangers' Club |
| Rankin Building |
| Rattlesnake Canyon Bridge |
| Ravenswood |
| Raymond-Summit Historic District |
| Rectory, Catholic Church of the Assumption |
| Redlands Santa Fe Depot District |
| Redman House |
| Redondo Beach Public Library |
| Red Rest and Red Roost Cottages |
| Redwood City Historic Commercial Buildings |
| Redwood Highway |
| Redwood Meadow Ranger Station |
| Reedley National Bank |
| Reedley Opera House Complex |
| Reed's Store |
| Reeve, Jennie A., House |
| Reilly |
| Rengstorff, Henry A., House |
| Renzel, Ernest & Emily, House |
| Rey, Valentine, House |
| Rhine House |
| Rhoades Ranch |
| Rialto Building |
| Rialto Theatre |
| Rice, Lilian Jenette, House |
| Richmond Shipyard Number Three |
| Ricks, Thomas F., House |
| Ridge Route, Old |
| Rincon Annex |
| Rindge, Frederick Hastings, House |
| Riverside-Arlington Heights Fruit Exchange |
| Riverside Municipal Auditorium and Soldier's Memorial Building |
| Rives, James C., House |
| Roberto-Sunol Adobe |
| Robinson, Elias H., House |
| Robinson, Virginia, Estate |
| Rockwell Field |
| Romain, Frank, House |
| Ronda |
| Roop's Fort |
| Roosevelt Building |
| Roos House |
| Rosebud Ranch |
| Rose Court |
| Rosecroft |
| Rosenburg's Department Store |
| Ross House |
| Round Valley Flour Mills |
| Rovegno, Charles, House |
| Rowland, John A., House |
| Royal Laundry Complex |
| Royal Presidio Chapel |
| Rozas House |
| Rubel Castle Historic District |
| Ruhstaller Building |
| Runyon House |
| Russian Hill-Macondray Lane District |
| Russian Hill-Paris Block Architectural District |
| Russian Hill-Vallejo Street Crest District |
| Russian Village District |
| Ryan House and Lost Horse Well |
Data from United States Park Service and Wikidata
