| 1 | PCA | Peace Air (Private) Limited | IATA: 6P, Callsign: Peace Air, | CL | AVCODES |
| 2 | PCA | P.C. Air Co., Ltd. | IATA: GT, Callsign: Piyo Air, Ceased operations. | T | AVCODES |
| 3 | PCA | Consolidated Rail Corp. | added 4/1976; 1/1980-1/1994; eliminated 7/1999 | | NAKINA |
| 4 | PCA | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/1976 | | NAKINA |
| 5 | PCA | Penn Central Transportation Co. | 1/1975 | | NAKINA |
| 6 | PCA | Penn Central Transportation Co. | Jan-75 | | NRHS |
| 7 | PCA | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | | NRHS |
| 8 | PCA | Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | | NRHS |
| 9 | PCA | *NORFOLK SOUTHERN RWY. [CONSOLIDATED RAIL CORP.; PENN CENTRAL TRANSPORTATION CO.] | | | PWRC |
| 10 | PCA | *PLANTERS COOP ASSOCIATION | | | PWRC |
| 11 | PCA | Penn Central (Norfolk Southern) | | | RSRV |
| 12 | PCAE | PACIFIC COASTAL EXPRESS | | | SCAC3 |
| 13 | PCAE | PASCAL LESSARD INC | | | SCAC4 |
| 14 | PCAF | PRECISIONAIRE INC | | | SCAC3 |
| 15 | PCAG | PENNY CARTAGE INC | | | SCAC3 |
| 16 | PCAG | PROMOTORA COMERCIAL DE LAS ARTES GR | | | SCAC4 |
| 17 | PCAI | PICARD, C A INTERNATIONAL | | | SCAC4 |
| 18 | PCAK | PAC ANCHOR TRANSPORTATION | | | SCAC4 |
| 19 | PCAL | PATRIOT CARRIERS LLC | | | SCAC4 |
| 20 | PCAM | PRICE AIRMOTIVE | | | SCAC4 |
| 21 | PCAN | PATERSON CANNING | | | SCAC3 |
| 22 | PCAO | PRO CARRIERS INC | | | SCAC4 |
| 23 | PCAP | PONCE TRANSPORT INC | | | SCAC4 |
| 24 | PCAR | PETES CUSTOM AUTO SERVICE | | | SCAC4 |
| 25 | PCAS | PACIFIC-ATLANTIC STEAMSHIP CO, | | | SCAC3 |
| 26 | PCAS | PACIFIC-ATLANTIC STEAMSHIP CO, | | | SCAC4 |
| 27 | PCAT | PACA TRANSPORT INC | | | SCAC3 |
| 28 | PCAU | GENERAL SERVICING AND TRADING LTD | | VAN | BIC |
| 29 | PCAV | PHILLIPS, J A TRUCKING LLC | | | SCAC4 |
| 30 | PCAX | Pioneer Chlor Alkali Co., Inc. | added 1/1991; 1/1994; eliminated 7/1994; added 10/1996; 7/2000; eliminated 4/2001; 7/2005 (not listed) | | NAKINA |
| 31 | PCAX | Pioneer Chlor Alkali Co., Inc. | added 1/91; 1/94; eliminated 7/94; added 10/96; 7/2000; eliminated 4/2001 | | NRHS |
| 32 | PCAX | PIONEER CHLOR ALKALI COMPANY, INC. | | | PWRC |
| 33 | PCAX | Pioneer Chlor Alkali | | | RSRV |
| 34 | PCAX | PIONEER CHLOR ALKALI COMPANY, INC. | | | SCAC4 |
| 35 | PCAY | POIRIER, CHRISTIAN TRANSPORT | | | SCAC4 |
| 36 | PCAZ | PCA INDUSTRY | | | PWRC |