| Baltimore Bullets | National Basketball Association | Baltimore | 1944 | Baltimore Coliseum |
| Baltimore Colts | — | Baltimore | 1947 | — |
| Baltimore Orioles | Major League Baseball | — | 1894 | Sportsman's Park, Oriole Park at Camden Yards, Lloyd Street Grounds, Memorial Stadium |
| Baltimore Ravens | National Football League | Baltimore | 1996 | Memorial Stadium, M&T Bank Stadium |
| Barcelona de Surquillo | Copa Perú | — | 8 September 1975 | Estadio Nacional del Perú (1897) |
| Basket Anagni | — | — | — | — |
| Basket Barcellona | — | Barcellona Pozzo di Gotto | 1976 | — |
| Basket Bees Treviglio | — | — | — | — |
| Basket Biassono | — | Biassono | — | — |
| Basket Brescia | — | Brescia | 1957 | — |
| Basket Cavezzo | — | Cavezzo | 1978 | — |
| Basket Cefalù | — | — | — | — |
| Basket Club Bolzano | — | Bolzano | — | Palazzetto dello sport "Paola Mazzali" |
| Basket Club Ferrara | — | Ferrara | 1999 | Palasport di Ferrara |
| Basket Club Valtarese 2000 | — | — | — | — |
| Basket Femminile Le Mura Lucca | — | Lucca | 2005 | — |
| Basket Femminile Livorno | — | Livorno | — | — |
| Basket Femminile Milano | — | Milan | — | — |
| Basket Femminile Pavia | — | — | — | — |
| Basket Fossombrone | — | Fossombrone | — | — |
| Basket Foxes Giussano | — | Giussano | 1983 | — |
| Basket Livorno | — | Livorno | 1947 | — |
| Basket Lumezzane | — | Lumezzane | — | — |
| Basket Massafra | — | Massafra | — | — |
| Basket Mestre 1958 | — | Mestre | 1958 | Vitrifrigo Arena |
| Basket Montichiari | — | — | — | — |
| Basket Parma | — | Parma | 1962 | — |
| Basket Recanati | — | Recanati | 1982 | — |
| Basket Rimini Crabs | — | — | — | — |
| Basket Team Crema | — | — | — | — |
| Basket Torino | — | Turin | 2019 | Palazzetto dello Sport Gianni Asti |
| Basketball Valdarno | — | — | — | — |
| Basketball Vigarano | — | Vigarano Mainarda | — | — |
| BC Castelnuovo Scrivia | — | Castelnuovo Scrivia | 1986 | — |
| BC Roma SPQR | Serie A | — | 2026 | Palazzetto dello Sport |
| Bears Mestre | — | Mestre | — | — |
| Bella Esperanza | Copa Perú | — | 1915 | — |
| Benedetto XIV Cento | — | San Lazzaro di Savena | 2011 | — |
| Bergamo Basket 2014 | — | Bergamo | 1970 | — |
| Blu Basket 1971 | — | Treviglio | 1971 | — |
| Bonfiglioli Ferrara Basket | — | Ferrara | — | — |
| Boston Braves | — | — | 1871 | — |
| Boston Bruins | — | — | 1924 | Matthews Arena, TD Garden, Boston Garden |
| Boston Celtics | National Basketball Association | Boston | 1946 | Matthews Arena, Boston Garden, PeoplesBank Arena, TD Garden |
| Boston Red Sox | Major League Baseball | Boston | 1901 | Huntington Avenue Grounds, Fenway Park |
| Brixia Basket | — | — | — | — |
| Brooklyn Americans | — | — | — | — |
| Brooklyn Dodgers | National League, American Association | — | — | — |
| Brooklyn Nets | National Basketball Association | Brooklyn | 1967 | Island Garden, Long Island Arena, Teaneck Armory, Prudential Center, Nassau Veterans Memorial Coliseum, Meadowlands Arena, Jersey Mike's Arena, Barclays Center |
| Buffalo Bills | National Football League | Orchard Park | 1960 | Ralph Wilson Stadium, War Memorial Stadium |
| Buffalo Sabres | — | — | 1970 | Buffalo Memorial Auditorium, KeyBank Center |