All - Architectural style - Federal architecture
| Cole-Evans House |
| Coleman, House |
| Coleman-White House |
| Colerain Forges Mansion |
| College Club Inn |
| College Hall |
| Collings-Knight Homestead |
| Collins, Isaac, House |
| Collins, Nathaniel Bishop, House |
| Collins, William, House |
| Colonial Hotel |
| Columbia |
| Columbia House |
| Columbia Turnpike-West Tollhouse |
| Colyer House, The |
| Commandant's Quarters |
| Community Place |
| Concord |
| Cone, Jared, House |
| Conger, Isaac, House |
| Connecticut Statehouse |
| Conner, Alexander, House |
| Conner, William, House |
| Constable Hall |
| Contentment |
| Conway House |
| Conwell, Elias, House |
| Cooke, Amos, House |
| Cooke, Noah, House |
| Cook House |
| Cook, John, House |
| Cool Hollow Home |
| Cool Spring Farm |
| Cool Spring Place |
| Cool Well |
| Cooper-Davenport Tavern Wing |
| Cooper, Thunise & Richard, House |
| Cooper, Tunis R., House |
| Copeland Carriage Shop |
| Corey, Timothy, House No. 1 |
| Corliss-Carrington House |
| Corning-White House |
| Corwin House |
| Cottage Gardens |
| Cottage Plantation |
| Cotton Hill |
| Cottrell House |
| Cottrill, Matthew, House |
| Coulter, George, House |
| Court Clerk's Office-County & Circuit |
| Courtland School |
| Cove Grove |
| Coventry Hall |
| Coverdale Cobblestone House |
| Cowdry, Jonas, House |
| Cowdry, William D., Plantation |
| Cowherd, Francis, House |
| Cowper-Thompson House |
| Cox, Gardner, House |
| Cox, Isaac, Cobblestone Farmstead |
| Crabill, David, House |
| Craighead-Jackson House |
| Craig-Peak House |
| Crandall, Prudence, House |
| Craver Farmstead |
| Crawford, John I, Farm |
| Crawford, Theophilus, House |
| Crawford-Whitehead-Ross House |
| Creekside |
| Creel, Elijah, House |
| Crocker, Lot, House |
| Crockett, Joseph, House |
| Cronkite, Jeremiah, House |
| Crosley-Garrett Mill Workers' Housing, Store and Mill Site |
| Crouse, Frederick, House |
| Crowell-Smith House |
| Crowley House |
| Crozet House |
| Crudup, Josiah, House |
| Crumley-Lynn-Lodge House |
| Cuckoo |
| Culbertson-Harbison Farm |
| Cullins-Baker House |
| Culong |
| Curtis, Noah, House |
| Cushing, Caleb, House |
| Cutter, Ephraim, House |
| Cutter, Gershom, House |
| Cutter, Jefferson, House |
| Daffin House |
| Dakin-Coleman Farm |
| Dalkeith |
| Dalton House |
| Daman, Rev. George, House |
| Damon, Joseph, House |
| Daniel, James and Cunningham, House |
| Dan's Hill |
| D'Antignac House |
| Davenport, Hanford, House |
| Davidson, Benjamin W., House |
Data from United States Park Service and Wikidata
