The Stockholm Open is a men's tennis tournament on the ATP Tour 250 that takes place in Stockholm, Sweden between the end of October and the beginning of November each year.
It is played on the hard courts of the Kungliga Lawntennisklubben, which also owns the tournament, and the main court is that of the Kungliga tennishallen sports hall. In 1975, 1979 and 1980, women's tournaments were also held in addition to the usual men's tournaments. It was voted by ATP tennis players as the best tournament in the ATP Tour 250 category in 2016 and 2018.
The Stockholm Open was founded in 1969 as a men's tournament on the initiative of former professional tennis player Sven Davidson and has been played at the Kungliga tennishallen since the first edition.
The Open Era had started the previous year and was the first Open Era tournament to be played indoors.
The Stockholm tournament retained some of its charm and in 2016 and 2018 was voted by ATP tennis players as the best tournament of the year in the ATP Tour 250 category, the new denomination of the ATP World Series. The 2020 edition was not held due to the COVID-19 pandemic.