| 2922 | Can forming machines, metalworking, manufacturing | |
| 2899 | Can keys, made from purchased wire | |
| 2899 | Can lids and ends, metal, manufacturing | |
| 2930 | Can openers, electric, domestic, manufacturing | |
| 2930 | Can openers, electric, manufacturing | |
| 2893 | Can openers, non-powered, manufacturing | |
| 6120 | Canal barge operations | |
| 4520 | Canal construction, contractors | |
| 6303 | Canal locks, operating | |
| 6303 | Canal operations | |
| 6120 | Canal transportation | |
| 4520 | Canals and related navigation facilities, construction | |
| 6303 | Canals maintenance (except dredging) | |
| 0111 | Canary seed farming | |
| 3000 | Canceling machinery, Post Office type, manufacturing | |
| 7512 | Cancer detection program administration, federal | |
| 7512 | Cancer detection program administration, government | |
| 7512 | Cancer detection program administration, state | |
| 8511 | Cancer hospital | |
| 7310 | Cancer research laboratories | |
| 2899 | Candelabra and candlesticks, metal (except precious metal), manufacturing | |
| 2102 | Candelabra tubes, made from purchased paperboard | |
| 1543 | Candied fruits and fruit peel, manufacturing | |
| 9241 | Candle pin bowling alleys | |
| 9241 | Candle pin bowling centres | |
| 5239 | Candle shops, retail | |
| 3150 | Candles, electric lighting fixtures, manufacturing | |
| 3699 | Candles, manufacturing | |
| 5139 | Candles, wholesale | |
| 1543 | Candy (except chocolate), manufacturing | |
| 1543 | Candy bars (except chocolate), manufacturing | |
| 1543 | Candy bars, chocolate (including chocolate-covered), made from cacao beans | |
| 1543 | Candy bars, chocolate (including chocolate-covered), made from purchased chocolate | |
| 1543 | Candy stores (except chocolate), candy made on the premises, not for immediate consumption | |
| 1543 | Candy stores, chocolate candy made on the premises, not for immediate consumption | |
| 5220 | Candy stores, retail | |
| 1543 | Candy, chocolate, made from cacao beans | |
| 1543 | Candy, chocolate, made from purchased chocolate | |
| 5122 | Candy, wholesale | |
| 5520 | Candy-floss trailer operations | |