| 1 | PTM | Southeastern Airways Corporation | Callsign: Postman, ICAO designator cancelled. | USA | AVCODES |
| 2 | PTM | Southeastern Airways | | | ICAO1 |
| 3 | PTM | ST Rail System | 7/2000-7/2005 | | NAKINA |
| 4 | PTM | Portland Terminal Co. | 1/1994; eliminated 10/1997 | | NAKINA |
| 5 | PTM | Portland Terminal Co. (Me.) | 1/1975-1/1980 | | NAKINA |
| 6 | PTM | Portland Terminal Co. | 10/1957-4/1970 | | NAKINA |
| 7 | PTM | Portland Terminal Co. | 10/57-4/70 | | NRHS |
| 8 | PTM | Portland Terminal Co. (Me.) | 1/75-1/80 | | NRHS |
| 9 | PTM | Portland Terminal Co. | 1/94; eliminated 10/97 | | NRHS |
| 10 | PTM | ST Rail System | Jul-00 | | NRHS |
| 11 | PTM | *(MEC) PORTLAND TERMINAL CO. | | | PWRC |
| 12 | PTM | +ST RAIL SYSTEM | | | PWRC |
| 13 | PTM | Portland Terminal (Pan Am Railways) | | | RSRV |
| 14 | PTM | Portland Terminal Co. | | USA | TRAFFIC |
| 15 | PTMA | PANSTAR SPECIAL MARITIME ENTERPRISE | | | SCAC4 |
| 16 | PTMB | PITTMAN BROTHERS TRANSPORTATION | | | SCAC3 |
| 17 | PTMC | PEEK, TIM & SON LLC | | | SCAC4 |
| 18 | PTME | PROMPT MOTOR EXPRESS | | | SCAC3 |
| 19 | PTME | PLACAS TERMODINAMICAS SA DE CV | | | SCAC4 |
| 20 | PTMG | PATHMARK TRANSPORTATION MARKETING C | | | SCAC3 |
| 21 | PTMH | PETERS MOBILE HOME TRANSPORTING | | | SCAC3 |
| 22 | PTMI | PEAVLER, T MOVING SYSTEMS | | | SCAC3 |
| 23 | PTMJ | PHILLIPS TOOL & MOULD LONDON LTD | | | SCAC4 |
| 24 | PTMK | PETROLEUM TERMINALS | | | SCAC3 |
| 25 | PTMK | PETROLEUM TERMINALS INC | | | SCAC4 |
| 26 | PTML | PRIME TIME DELIVERY | | | SCAC4 |
| 27 | PTMM | PALOMAR TRANSIT MIX CO | | | SCAC3 |
| 28 | PTMM | PT MERANTI MARITIME | | | SCAC4 |
| 29 | PTMN | PITTMAN, ROBERT L, MOVING & STRGE | | | SCAC3 |
| 30 | PTMN | PITTMAN, M ENTERPRISES L C | | | SCAC4 |
| 31 | PTMO | PROTECTIVE TREATMENTS INC | | | SCAC3 |
| 32 | PTMO | PTM COURIER | | | SCAC4 |
| 33 | PTMQ | PRIME TIME TOURS | | | SCAC3 |
| 34 | PTMQ | PETROMARINE | | | SCAC4 |
| 35 | PTMR | PORT MARINE SERVICES INC | | | SCAC3 |
| 36 | PTMR | PLANTATION M R | | | SCAC4 |
| 37 | PTMS | PRIME TIME MESSENGER INC | | | SCAC4 |
| 38 | PTMT | PORTLAND MOTOR TRANSPORT | | | SCAC3 |
| 39 | PTMT | PORTLAND MOTOR TRANSPORT | | | SCAC4 |
| 40 | PTMV | PITTMAN, VERNON VAN LINES INC | | | SCAC3 |
| 41 | PTMV | PETROMAR LIMITED | | | SCAC4 |
| 42 | PTMW | PROSSER, JAMES W | | | SCAC3 |
| 43 | PTMX | Pittsburgh Transportation Museum Society | 7/2005 (not listed) | | NAKINA |
| 44 | PTMX | PITTSBURGH TRANSPORTATION MUSEUM SOCIETY | | | PWRC |
| 45 | PTMX | Pittsburgh Transportation Museum Society | | | RSRV |
| 46 | PTMX | PITTSBURGH TRANSPORTATION MUSEUM SO | | | SCAC4 |
| 47 | PTMY | PROTEUS MANAGEMENT COMPANY INC | | | SCAC3 |
