Connecticut - Criteria: C (architecture/engineering)
| Warren Congregational Church |
| Warrenton Woolen Mill |
| Washington Avenue Bridge |
| Washington Bridge |
| Washington Green Historic District |
| Washington School |
| Washington Street Historic District |
| Washington Street School |
| Waterbury Clock Company |
| Waterbury Municipal Center Complex |
| Waterbury Union Station |
| Water Street Historic District |
| Watertown Center Historic District |
| Watkinson Juvenile Asylum and Farm School |
| Wauregan Historic District |
| Webb, David Jr. and Sarah, House |
| Webb, Joseph, House |
| Webster, Horace, Farmhouse |
| Webster Memorial Building |
| Webster, Noah, Memorial Library |
| Webster School |
| Welch, David, House |
| Welch Training School |
| Welles, Gideon, House |
| Welles-Shipman-Ward House |
| Wells, John, Jr., House |
| West Boulevard Historic District |
| Westbrook Town Center Historic District |
| West Cornwall Bridge |
| West End Commercial District |
| West End Congregation-Achavath Achim Synagogue |
| West End Historic District |
| West End Library |
| West End North Historic District |
| West End South Historic District |
| West Goshen Historic District |
| West Granby Historic District |
| West Haven Green Historic District |
| West Hill Historic District |
| West Mountain Historic District |
| Westport Bank and Trust Company |
| West Street School |
| Westville Village Historic District |
| Wethersfield Avenue Car Barn |
| Wetmore, Seth, House |
| Whale Oil Row |
| Wheeler, Adin, House and Theodore F. Wheeler Wheelwright Shop |
| Wheeler-Beecher House |
| Wheeler Block |
| Wheeler, Ephraim, House |
| Wheeler, Jonathan, House |
| Whitehall Mansion |
| White-Overton-Callander House |
| White's Tavern |
| Whitfield Cowles House |
| Whitfield, Henry, House |
| Whiting Homestead |
| Whitman House |
| Whitney Avenue Historic District |
| Whitneyville Congregational Church |
| Whittlesey, Ambrose, House |
| Whittlesey, John, Jr., House |
| Wiard, John, House |
| Wickham Road Historic District |
| Widows' Home |
| Wightman, Rev. John, House |
| Wightman, Valentine, House |
| Wilby High School |
| Wilcox, Crittenden Mill |
| Wilcox, Josiah, House |
| Wildman, E. A., & Co. Tobacco Warehouse |
| Willard Homestead |
| William Clark Company Thread Mill |
| Williams and Stancliff Octagon Houses |
| Williams, Captain Benjamin House |
| Williams, Eleazer, House |
| Williams House |
| Williams, J. B., Co. Historic District |
| Williams Memorial Institute |
| Williams Memorial Park Historic District |
| Williams, Warham, House |
| Willimantic Armory |
| Willimantic Elks Club |
| Willimantic Footbridge |
| Willimantic Freight House and Office |
| Willington Common Historic District |
| Wilson, John, House |
| Wilton Center Historic District |
| Winchester Repeating Arms Company Historic District |
| Winchester Soldiers' Monument |
| Windham Center Historic District |
| Windsor Avenue Congregational Church |
| Windsor Farms Historic District |
| Windsor Locks Passenger Station |
| Winsted Green Historic District |
| Winsted Hosiery Mill |
| Winthrop Mill |
| Witter House |
| Wolcott Green Historic District |
| Woodbridge Farm |
Data from United States Park Service and Wikidata
