- Cohen Brothers Realty and Construction Corp.11
- Cohn Brothers12
- Cohn, Herman M.1
- Cole & Gilpin1
- Cole, H.M.1
- Collins Plow Company1
- Collins, Tuttle and Co.16
- Colonial Towers, Inc.2
- Columbia Bank1
- Columbia Machine Works1
- Columbia National Bank1
- Columbia Skirt Co.1
- Columbia-Clark Corp.6
- Colwell Lead Company2
- Commonwealth Syndicate, Inc.1
- Compton Estates, Inc.1
- Conco Realty Corp.1
- Concord Hall, Inc.1
- Concord Village Co.3
- Concourse Building Corp.1
- Concourse Crescent Corp.1
- Concourse Development, Inc.1
- Concourse Properties, Inc.1
- Concourse and 181st Street Corp.1
- Congdon & Carpenter Co.1
- Conley, Kirk & Co.1
- Construction and Development Corp. of New York1
- Continental Life Insurance Company1
- Continental Paper Bag Co.1
- Convent Gardens, Inc.1
- Cook & Bernheimer Co.1
- Cook House1
- Cooper-Bregstein Realty Co.9
- Coral Gardens, Inc.1
- Cord-Meyer Development Co.12
- Cornet & Nightengale1
- Cornish Arms, Inc.1
- Coronet Realty, Inc.1
- Cosmopolitan Associates1
- Cosmopolitan Hotel2
- Court and Remsen Building Corp.10
- Courtlandt Street Hotel1
- Cousens & Tomlinson1
- Cowing & Co.1
- Craddock-Terry Company1
- Craffey and Crowell1
- Crandall & Morrison2
- Crandall, Edward H.1
- Crane & Hurd3
- Crausman, I.L.20
- Crescent Candy Company1
- Creston Building Corp.1
- Creston Realty Corp.1
- Crislou Realty Corp.1
- Crocheron Gardens, Inc.1
- Crocker & Eldridge1
- Crocker & Ogden1
- Croft Brothers1
- Cross & Brown Company1
- Cross Properties, Inc.24