New York - Criteria: C (architecture/engineering)
| Comstock, Nathan, Jr., House |
| Comstock, Zephnia, Farmhouse |
| Conant, Austin R., House |
| Concklin, Abner, House |
| Concourse Yard Entry Buildings |
| Concourse Yard Substation |
| Concrete-Central Elevator |
| Conesus Amusement Hall |
| Coney Island Fire Station Pumping Station |
| Coney Island Yard Electric Motor Repair Shop |
| Coney Island Yard Gatehouse |
| Congdon, Hiram, House |
| Congregation Ahavas Achim Anshi Austria |
| Congregational Church |
| Congregational Church of Patchogue |
| Congregational Church of the Evangel |
| Congregation Beth Abraham |
| Congregation Bnai Israel Synagogue |
| Congregation B'nai Jeshurun Synagogue and Community House |
| Congregation Chevra Linath Hazedeck |
| Congregation Ohab Zedek |
| Congregation Shaare Zedek of Harlem |
| Congregation Tifereth Israel |
| Congregation Tifereth Israel |
| Congregation Tifereth Israel Synagogue |
| Congregation Tifereth Yehuda Veyisroel |
| Conkey House |
| Conklin, David, House |
| Conklin Farm |
| Conklin Mountain House |
| Conklin, Nathaniel, House |
| Conklin Town Hall |
| Connecticut Street Armory |
| Connors, William, Paint Manufacturing Company Building |
| Constable Hall |
| Constableville Village Historic District |
| Contempora House |
| Control House on 72nd Street |
| Coolidge Stores Building |
| Coons, Charles H., Farm |
| Coons House |
| Cooper Avenue Row Historic District |
| Cooperstown Historic District |
| Copake Falls Methodist Episcopal Church |
| Copake Grange Hall |
| Copake Iron Works Historic District |
| Copake Memorial Clock |
| Copake United Methodist Church and Copake Cemetery |
| Copcutt,John,Mansion |
| Copeland Carriage Shop |
| Copeland Covered Bridge |
| Coppola House |
| Corbin Building |
| Corby Farm Complex |
| Cordts Mansion |
| Corlies-Ritter-Hart House |
| Cornelia-Putnam Historic District |
| Cornell Farmhouse |
| Cornell Heights Historic District |
| Cornell-Manchester Farmstead |
| Cornell-Van Nostrand House |
| Cornfield, The |
| Corning Armory |
| Cornwall Friends Meeting House |
| Corpus Christi R.C. Church Complex |
| Cortland County Courthouse |
| Cortland County Poor Farm |
| Cortland Fire Headquarters |
| Cortland Free Library |
| Corwith, William, House |
| Cottage Farm |
| Cottage in the Pines |
| Cottage Lawn |
| Cottage Row Historic District |
| Cottages at Central Point |
| Coulter Cottage |
| County and City Hall |
| Courier Building, The |
| Court Exchange Building-National Casket Company |
| Court Street Bridge |
| Court Street Historic District |
| Court Street Historic District |
| Coverdale Cobblestone House |
| Covert Historic District |
| Covert, William, Cobblestone Farmhouse |
| Covewood Lodge |
| Cowles, W.T., House |
| Cox-Budlong House |
| Cox Building |
| Cox Farmhouse |
| Cox, Gardner, House |
| Cox, Isaac, Cobblestone Farmstead |
| Cox, Richard, House |
| Coykendall Lodge |
| Crabtree, John A., House |
| Cragsmoor Historic District |
| Cragston Dependencies |
| Cramer, Frederick, House |
| Crandall Farm Complex |
| Crandall Marine Railway |
Data from United States Park Service and Wikidata
