The Portuguese Primeira Liga is the highest level of professional football in Portugal. It was founded in 1934 and 18 teams compete in it. Only five of them have won the championship. The league is dominated by the "Big Three" - FC Porto, Benfica and Sporting Lisbon. They have a total of 82 championship titles. The other two titles are divided between Boavista and Belenenses.

Each of the 18 teams plays against each other in two matches - as a host and as a guest. A total of 34 rounds are played. After the end, the last three teams in the standings are relegated to the second level of Portuguese football - the Liga de Onra. The Primera Division Champions play in the Champions League groups. The team in second place plays qualifiers. The third team and the fourth team play qualifiers for the Europa League.

The Primera League is ranked 5th in the UEFA rankings in Europe.

Benfica has the most championship titles - a total of 36. After that is Porto with 28. In the third place is Sporting with 18, followed by Belenenses and Boavista with one title each. Benfica is also in first place in the eternal ranking of the Primeira League.

In 1972/73 Benfica became the first team to win the Portuguese league undefeated with 58 points in 30 games (28 wins and 2 draws), while at that time 2 points were given for victory. In the same season, the team set a national and European record for the most consecutive victories - 23. From October 24, 1976 to September 1, 1978, Benfica set a record for the longest unbeaten streak in the league - 56 matches. In 2010/11 and 2012/13 Porto also managed to finish the league without losses.