Ohio - Criteria: C (architecture/engineering)
| Buckeye State Building and Loan Company Building |
| Buckeye Station |
| Buckland, Ralph P., House |
| Buckner, Dr. Philip, House And Barn |
| Bucyrus Commercial Historic District |
| Bucyrus Mausoleum |
| Budd Dairy Company |
| Buehl House |
| Building at 101 North Franklin Street |
| Building at 223 West High Street |
| Building at 240 Park Avenue West |
| Building at 252-254 Park Avenue West |
| Building at 309 Park Avenue West |
| Building at 3101 Euclid Avenue |
| Building at 415 Park Avenue West |
| Building at 500 East High Street |
| Building at 620-622 Vine Street |
| Bullerdick, Frederick E. and Catherine, House |
| Bull, Jonah, House |
| Bull, T.J. and Sarah, House |
| Bunker Hill House |
| Burckhardt, A. E., House |
| Burdick, Harold B., House |
| Burdsal, Samuel, House |
| Burnett, William, House |
| Burnham, Henry, House |
| Burrell, Jabez and Robbins, House and Cheese Factory |
| Burrell-King House |
| Burr, George, House |
| Burroughs, C. H., House |
| Burt's Theater |
| Burt, William, House |
| Bushnell, Martin, House |
| Bush, Samuel, House |
| Butler, Charles, House |
| Butler County Courthouse |
| Butler, Cyrus, House |
| Butler Institute Of American Art |
| Butler, J.G., House |
| Buttles, Aurora, House |
| Buttles-Johnson House |
| Buxton Inn |
| Byer Covered Bridge |
| Byers, John F., House |
| Cable, Frank, House |
| Cable, Laurence House |
| Cahill, Beck and R. C., Buildings |
| Cahill, Michael, House |
| Cahoon, Samuel C., House |
| Caledonia Bowstring Bridge |
| Calvary Episcopal Church Sunday School |
| Cambridge Arms |
| Camden City Hall and Opera House |
| Camden Public School |
| Campbell, Hugh, House |
| Campbell School |
| Camp Manatoc Dining Hall |
| Camp Manatoc Legion Lodge |
| Canal Winchester Methodist Church |
| Canton Public Library |
| Capital University Historic District |
| Capt. Stone House |
| Carew Tower |
| Carkhuff, Stacy G., House |
| Carnegie Library |
| Carnegie Library and Henry St. Clair Memorial Hall |
| Carnegie Library of Steubenville |
| Carnegie Public Library |
| Carpenter, Wallace W., House |
| Carroll County Courthouse |
| Carroll Township Hall |
| Carty, J.-R. J. Tussing House |
| Cary, G.W., House |
| Cary, Hiram W., House |
| Cascade Locks Historic District |
| Cassella Catholic Church and Rectory |
| Cassell, Henry, House |
| Casstown Lutheran Stone Church |
| Casterton House |
| Cawood, Richard L., Residence |
| Caxton Building |
| Cedar Glen Apartments |
| Cedar Hill Cemetery Buildings |
| Cedar Point Light |
| Cedarville Opera House |
| Center Inn |
| Center Street Historic District |
| Central Assurance Company |
| Central Avenue Historic District |
| Central Branch, National Home for Disabled Volunteer Soldiers |
| Central Building of the Columbus Young Men's Christian Association |
| Central College Presbyterian Church |
| Central High School |
| Central High School |
| Central Hotel, Hackedorn and Zimmerman Building |
| Central Ohio Lunatic Asylum |
| Central School |
| Central Tower Building |
| Central United Methodist Church |
| Central YMCA |
Data from United States Park Service and Wikidata
