C.F. Os Belenenses

Founded in 1919, it reached its first Campeonato final in 1926, losing 2–0 to Marítimo, and won the title the next season with a 3–0 win over Vitória de Setúbal and winning a second championship in 1929. The club lost the 1932 title to Porto 2–1 in a replay after a 4–4 draw. The club won its third and final Campeonato in 1933 after defeating Sporting CP 3–1.[3] With three Campeonato wins, Belenenses was one of Portugal's "Big Four". Since the advent of the Primeira Liga, Os Belenenses has failed to keep up with the other three clubs (Benfica, FC Porto and Sporting CP).

The club won its only Primeira Liga title in 1945–46, edging Benfica by one point,[4] the first time that a club outside the Big Three won the title. On 14 December 1947, they were the first team to face Real Madrid at their newly inaugurated Santiago Bernabéu Stadium (then called the Nuevo Estadio Chamartín) in a friendly match won 3–1 by Madrid.[5] The club were runners-up in the league for the first time in the 1954–55 season, level on 39 points with Benfica.[6] It was not until 1973 that Belenenses finished runner-up again, 18 points behind Benfica, and they never have since.[7]

Belenenses were the first club to compete in the UEFA Cup in a two-legged 3–3 draw with Hibernian at the Estádio do Restelo in Belém.

The club has also played in the European Cup Winners' Cup. In the 1987–88 UEFA Cup, the club played Barcelona. In the first leg, they lost 2–0 in the Camp Nou, winning 1–0 at the Estádio do Restelo with Mapuata scoring. Belenenses won their sixth (and to date last) Taça de Portugal on 28 May 1989, defeating Benfica 2–1.[8] Also that season, they knocked out the holders Bayer Leverkusen from the Cup Winners' Cup.

Belenenses were relegated from the Primeira Liga for the first time in 1981–82, and have been relegated three other times since then.

The 2005–06 season saw Belenenses finishing fourth from bottom, which would mean relegation for the team. However, as Gil Vicente had fielded an ineligible player that season, Belenenses won a subsequent appeal which saw them remain in the top division with Gil Vincente being relegated instead.[9] On 27 May 2007, Belenenses reached their first Taça de Portugal final since their 1989 triumph, but were defeated 1–0 by Sporting CP.[10]

Cabral Ferreira, who served as club president of Belenenses from 2005 until 2008, died on 26 February 2008 after a long illness.[11] Belenenses were relegated in 2010 to the Segunda Liga, but secured promotion back to the Primeira Liga in March 2013, their longest stint out of the top division.

During the 2014–15 season, Belenenses finished the championship in sixth place, thereby returning to European competition, qualifying for the 2015–16 UEFA Europa League.

They reached the group stage of the 2015–16 UEFA Europa League after eliminating IFK Göteborg (2–1 on aggregate) and Rheindorf Altach (1–0 on aggregate). They finished fourth and last in their group, recording a surprising 2–1 away win against Basel, but drawing 0–0 twice against Lech Poznań, losing the return match against Basel, and losing both matches to Fiorentina.

At the end of 2017–18 season, CF os Belenenses (Club) and Belenenses SAD went their separate ways, as the "Protocol on the use of Estádio do Restelo" ended and the SAD refused to negotiate a new contract with the club. So from the 2018–19 season, Belenenses SAD (the professional team) play their Primeira Liga home games at Estádio Nacional, whereas CF os Belenenses registered an amateur team in 1ª Divisão Distrital de Lisboa, the equivalent to the Sixth Division (lowest Portuguese division), with the support of the majority of fans and club members.

As a consequence, Belenenses SAD was legally forbidden from using Belenenses' Logo and name and now uses a new logo (Along with being renamed to B-SAD after the 2021/22 season).[12] In the first games of the season, the professional team saw home attendances of only a few hundred, whereas the new, amateur team saw home attendances of approximately 5,000, reversing a long decline in attendance figures.[13]

• Primeira Liga

Winners (1): 1945–46

• Taça de Portugal

Winners (3): 1941–42, 1959–60, 1988–89

Runners-up (5): 1939–40, 1940–41, 1947–48, 1985–86, 2006–07

• Supertaça Cândido de Oliveira

Runners-up (1): 1989

• Campeonato de Portugal[14]

Winners (3): 1926–27, 1928–29, 1932–33

Runners-up (3): 1925–26, 1931–32, 1935–36

• Segunda Divisão / Segunda Liga

Winners (2): 1983–84, 2012–13

• Lisbon FA 1ª Divisão

Winners (2): 2018–19, 2020–21

• Lisbon Championship

Winners (6): 1925–26, 1928–29, 1929–30, 1931–32, 1943–44, 1945–46

• Intertoto Cup

Winners (1): 1975