| Port Code | Port Name | Country |
| ITNVO | Nuova Olonio | Italy |
| ITNVR | Novara | Italy |
| ITNVT | Novedrate | Italy |
| ITOAS | Orio Al Serio | Italy |
| ITOBS | Orbassano | Italy |
| ITOCI | Occhieppo Inferiore | Italy |
| ITOCO | Occimiano | Italy |
| ITOCS | Oggiona con Santo Stefano | Italy |
| ITODL | Odolo | Italy |
| ITODZ | Oderzo | Italy |
| ITOEN | None | Italy |
| ITOEO | Offanengo | Italy |
| ITOGG | Oggiono | Italy |
| ITOGI | Oleggio Castello | Italy |
| ITOGL | Ogliastro Cilento | Italy |
| ITOHB | Occhiobello | Italy |
| ITOLA | Parola | Italy |
| ITOLB | Olbia | Italy |
| ITOLC | Olgiate Comasco | Italy |
| ITOLE | Oleggio | Italy |
| ITOLG | Olginate | Italy |
| ITOLM | Olmo al Brembo | Italy |
| ITOLO | Olona | Italy |
| ITOMG | Omegna | Italy |
| ITOMM | Oste-Montemurlo | Italy |
| ITOMO | Como | Italy |
| ITONE | Oneglia | Italy |
| ITONN | Osmannoro | Italy |
| ITONO | Ottana | Italy |
| ITONR | Onara | Italy |
| ITONT | Montà D'Alba | Italy |
| ITONV | Conversano | Italy |
| ITOPD | Ospedaletti | Italy |
| ITOPL | Ospedaletto Lodigiano | Italy |
| ITOPP | Oppeano | Italy |
| ITOPR | Opera | Italy |
| ITORA | Ora | Italy |
| ITORE | Orte | Italy |
| ITORG | Origgio | Italy |
| ITORI | Orio Litta (Milano) | Italy |
| ITORM | Ormelle | Italy |
| ITORN | Ortonovo | Italy |
| ITORR | Cornaredo | Italy |
| ITORT | Orta Nova | Italy |
| ITORV | Orvieto | Italy |
| ITORZ | Orzinuovi | Italy |
| ITOSE | Coseano | Italy |
| ITOSG | Orsago | Italy |
| ITOSI | Osio Di Sopra | Italy |
| ITOSM | Osimo | Italy |
| ITOSN | Osnago | Italy |
| ITOSO | Ospedaletto | Italy |
| ITOSP | Ospitaletto | Italy |
| ITOSS | Osio Sotto | Italy |
| ITOST | Osteria Grande | Italy |
| ITOSU | Ostuni | Italy |
| ITOTA | Prato | Italy |
| ITOTN | Ortona | Italy |
| ITOTO | Otranto | Italy |
| ITOTT | Castellana Grotte | Italy |
| ITOTV | Ottaviano | Italy |
| ITOVD | Ovada | Italy |
| ITOVO | Casalnuovo di Napoli | Italy |
| ITOZE | Ozzano dell'Emilia | Italy |
| ITPAA | Paruzzaro | Italy |
| ITPAC | Pachino | Italy |
| ITPAD | Paladina | Italy |
| ITPAE | Ponte a Evola | Italy |
| ITPAG | Campagna | Italy |
| ITPAI | Pagani | Italy |
| ITPAL | Palazzolo dello Stella | Italy |
| ITPAM | Ponte a Moriano | Italy |
| ITPAN | Panarea | Italy |
| ITPAO | Passirano | Italy |
| ITPAP | Paderno Ponchielli | Italy |
| ITPAR | Paratico | Italy |
| ITPAS | Paolisi | Italy |
| ITPAU | Palau | Italy |
| ITPAV | Pavia | Italy |
| ITPAZ | Porto Azzurro | Italy |
| ITPBA | Santa Palomba | Italy |
| ITPCA | Pescia | Italy |
| ITPCB | Pessano con Bornago | Italy |
| ITPCE | Porto Cervo | Italy |
| ITPCH | Peschici | Italy |
| ITPCM | Portacomaro | Italy |
| ITPCO | Percoto | Italy |
| ITPCS | Porto Corsini | Italy |
| ITPCZ | Piacenza | Italy |
| ITPDA | Padova | Italy |
| ITPDC | Pieve di Cento | Italy |
| ITPDD | Paderno Dugnano | Italy |
| ITPDG | Pove del Grappa | Italy |
| ITPDI | Porto d'Ischia | Italy |
| ITPDL | Ponte dell'Olio | Italy |
| ITPDM | Pradamano | Italy |
| ITPDO | Pandino | Italy |
| ITPDP | Prata di Pordenone | Italy |
| ITPDS | Porto d'Ascoli | Italy |
| ITPDU | Pavia di Udine | Italy |