| Potenza 84 | — | Potenza | — | — |
| Progresso Castel Maggiore | — | Castel Maggiore | — | — |
| Quebec Bulldogs | — | — | 1888 | Quebec Skating Rink |
| Racing de Huamachuco | Copa Perú | — | 1946 | — |
| Raggisolaris Faenza | — | Faenza | — | — |
| Real Salt Lake | Major League Soccer | Salt Lake City | 2005 | America First Field |
| Real Sebastiani Rieti | Serie A2 Basket | Rieti | 2020 | — |
| Red Bull New York | Major League Soccer | Harrison | 1995 | Giants Stadium, Sports Illustrated Stadium |
| Regatas Lima | Copa Perú | — | — | — |
| Reyer Venezia Mestre | Serie A | Venice | 1925 | Palasport Taliercio |
| Reyer Venezia Mestre Femminile | — | Venice | 1925 | — |
| Riva del Garda Basket | — | Riva del Garda | — | — |
| Riviera Vado Basket | — | — | — | — |
| Robur Basket Osimo | — | Osimo | — | — |
| Robur et Fides Varese | — | Varese | — | — |
| Rovereto Basket | — | Rovereto | — | — |
| S.S. Basket Napoli | — | Naples | 1946 | PalaBarbuto |
| Saetas de Oro | Copa Perú | — | — | — |
| San Antonio Spurs | National Basketball Association | — | 1967 | Alamodome, Kay Bailey Hutchison Convention Center, HemisFair Arena, Fort Worth Convention Center, Frost Bank Center, Moody Coliseum, Lubbock Municipal Coliseum |
| San Diego FC | Major League Soccer | San Diego | 18 May 2023 | Snapdragon Stadium |
| San Diego Padres | Major League Baseball | San Diego | 1969 | Petco Park |
| San Francisco 49ers | National Football League | — | 1946 | Levi's Stadium |
| San Francisco de Asís de Lonya Grande | Copa Perú | — | 1946 | — |
| San Francisco Giants | Major League Baseball | San Francisco | 1883 | Oracle Park |
| San Jose Earthquakes | Major League Soccer | San Jose | 1995 | PayPal Park, Stevens Stadium |
| San Jose Sharks | — | — | 1991 | Cow Palace, SAP Center |
| San Lorenzo de Almagro de Chiclayo | Copa Perú | — | — | Estadio Elías Aguirre |
| San Martino di Lupari | — | — | — | — |
| San Martín de Porres de Pucallpa | Copa Perú | — | 9 April 1964 | Estadio Aliardo Soria Pérez |
| San Simón de Moquegua | Peruvian Primera División | — | 1983 | Estadio 25 de Noviembre |
| Santiago Barranco | Copa Perú | — | 20 September 1929 | — |
| Santos de Nasca | Copa Perú | — | — | Estadio José Picasso Peratta |
| Scafati Basket | Serie A | Scafati | 1969 | PalaMangano |
| Seattle Kraken | — | — | 2021 | Climate Pledge Arena |
| Seattle Mariners | Major League Baseball | — | 1977 | Kingdome, T-Mobile Park |
| Seattle Metropolitans | Pacific Coast Hockey League | Seattle | 1915 | — |
| Seattle Seahawks | National Football League | — | 1976 | Kingdome, Husky Stadium, Lumen Field |
| Seattle Sounders FC | Major League Soccer | Seattle | 2009 | Lumen Field |
| Seattle SuperSonics | — | Washington | 1967 | Kingdome, Climate Pledge Arena, Tacoma Dome |
| Sebastiani Basket Club Rieti | — | — | — | — |
| Senati FBC | Copa Perú | — | — | Estadio Mariano Melgar |
| Serrato Pacasmayo | Peruvian Segunda División | — | 2012 | Estadio Carlos A. Olivares |
| Sheboygan Redskins | National Basketball Association | Sheboygan | 1938 | Playdium, Sheboygan Municipal Auditorium and Armory |
| Sisv Viterbo | — | Viterbo | — | — |
| Societa Veroli Basket | — | Frosinone | 1968 | — |
| Società Cestistica Mazzini | — | Bologna | — | — |
| Società Ginnastica Triestina | — | Trieste | 1930 | — |
| Spider Fabriano | — | — | — | — |