| 1 | PPU | Polish Air Navigation Services Agency | Callsign: Papuga, | PL | AVCODES |
| 2 | PPU | Tazewell & Peoria R.R. | added 4/2005; 7/2005 | | NAKINA |
| 3 | PPU | Tazewell & Pekin R.R. | added 1/2005 | | NAKINA |
| 4 | PPU | Peoria & Pekin Union Ry. Co. | 7/1965-7/2000; eliminated 1/2005; eliminated 4/2005 | | NAKINA |
| 5 | PPU | Peoria & Pekin Union Ry. Co. | 7/65-7/2000 | | NRHS |
| 6 | PPU | TAZEWELL & PEORIA RAILROAD [PEORIA & PEKIN UNION RAILWAY CO.] | | | PWRC |
| 7 | PPU | Peoria and Pekin Union Railway | | | RSRV |
| 8 | PPU | Peoria and Pekin Union | | USA | TRAFFIC |
| 9 | PPUD | PAPPYS PICKUP & DELIVERY | | | SCAC3 |
| 10 | PPUP | PEGASUS PICK-UP AND DELIVERY SERVIC | | | SCAC3 |
| 11 | PPUQ | PERSONALIZED PICK-UP SERVICE, INC | | | SCAC3 |
| 12 | PPUQ | PERSONALIZED PICK-UP SERVICE | | | SCAC4 |
