| Nuova Pallacanestro Vigevano | — | Vigevano | 1955 | — |
| OBG Roma | — | — | — | — |
| Oklahoma City Thunder | National Basketball Association | Oklahoma City | 2008 | Climate Pledge Arena, Tacoma Dome, Paycom Center, Kingdome |
| Oleggio Magic Basket | — | Oleggio | — | — |
| Olimpia Basket Matera | — | Matera | 1960 | — |
| Olimpia Cagliari | — | Cagliari | 1953 | — |
| Olimpia Milão | Liga Italiana de Basquetebol | Milão | 1936 | Mediolanum Forum |
| Olympia 68 Basketball | — | Reggio di Calabria | — | — |
| Orlando Magic | National Basketball Association | Orlando | 1989 | Amway Arena, Kia Center |
| Pallacanestro Ares Palermo | — | Palermo | — | — |
| Pallacanestro Aurora Desio | — | Desio | 1994 | — |
| Pallacanestro Broni 93 | — | — | — | — |
| Pallacanestro Cantù | Liga Italiana de Basquetebol | Cermenate | 1936 | Palasport Pianella |
| Pallacanestro Chieti | — | Chieti | 1989 | — |
| Pallacanestro Don Bosco Livorno | — | — | — | — |
| Pallacanestro Femminile Costone | — | — | — | — |
| Pallacanestro Firenze | — | Florença | 1948 | — |
| Pallacanestro Forlì 2015 | — | Forlì | 1946 | Unieuro Arena |
| Pallacanestro Gallaratese | — | — | — | — |
| Pallacanestro Interclub | — | — | — | — |
| Pallacanestro Lago Maggiore | — | — | — | — |
| Pallacanestro Lucca | — | Lucca | — | — |
| Pallacanestro Mantovana | — | Mântua | 2004 | — |
| Pallacanestro Marsala | — | — | — | — |
| Pallacanestro Messina | — | Messina | 1976 | — |
| Pallacanestro Milano 1958 | — | Milão | 1957 | — |
| Pallacanestro Palestrina | — | — | — | — |
| Pallacanestro Pavia | — | Pavia | 1943 | — |
| Pallacanestro Piacentina | — | Piacenza | 2011 | — |
| Pallacanestro Pozzuoli | — | — | — | — |
| Pallacanestro Ribera | — | — | 1969 | — |
| Pallacanestro Sanga Milano | — | Milão | — | — |
| Pallacanestro Sant'Antimo | — | Sant'Antimo | 1989 | — |
| Pallacanestro Treviso | Liga Italiana de Basquetebol | Treviso | 1954 | Palaverde |
| Pallacanestro Trieste 2004 | Liga Italiana de Basquetebol | Trieste | 1975 | Palatrieste |
| Pallacanestro Virtus Cassino | — | Frosinone | 2011 | — |
| Palmares Catania | — | Catânia | — | — |
| Partenio Avellino | — | — | — | — |
| Partenope Napoli | — | Sant'Antimo | 1957 | — |
| PB63 Lady | — | — | 1963 | — |
| Perugia Basket | — | — | — | — |
| Pescara Basket | Serie C (Italian men's basketball league) | Pescara | — | PalaElettra |
| PF Schio | — | Schio | 1973 | — |
| PF Umbertide | — | Umbertide | 2008 | — |
| Philadelphia 76ers | National Basketball Association | Filadélfia | 1946 | Xfinity Mobile Arena, Toyota Coliseum, Philadelphia Arena, Spectrum (arena), Philadelphia Convention Hall and Civic Center, Oncenter War Memorial Arena |
| Phoenix Suns | National Basketball Association | Phoenix | 1968 | Arizona Veterans Memorial Coliseum, Footprint Center |
| Pistoia Basket 2000 | Liga Italiana de Basquetebol | Pistoia | 2000 | PalaFermi |
| PMS Basketball | — | Moncalieri | — | — |