Based on Slovenia's Adriatic coast, FC Koper is one of the oldest football clubs in the country's coastal region. Organised football in Koper dates back to 1920, when Circolo Sportivo Capodistriano was established by local students, workers and fishermen. The club went through several changes of name and structure over the following decades, while the modern name NK Koper emerged in the mid-1950s after the merger of the local sports associations Aurora and Meduza.
The club's history is connected not only with Slovenian football but also with the sporting history of the wider Istrian region. Before the Second World War, Koper competed in competitions organised in the territory of the Julian March. After the establishment of Yugoslavia, the club played within that country's football system, and in 1981 it reached the highest level of the Slovenian republican competition. Koper subsequently won the Slovenian republican championship, although this was not the same as winning the Yugoslav federal championship.
The defining moment in FC Koper's history came in the 2009/10 season. Under coach Nedžad Okčić, the club won its first and so far only Slovenian championship. Koper secured the title with four matches remaining by defeating Rudar Velenje 2–0 away from home. Experienced midfielder Miran Pavlin played an important role as captain and also influenced the team in his position as sporting director. Koper finished the campaign with 73 points, 11 ahead of Maribor. The club also won the Slovenian Super Cup that year.
The championship earned Koper a place in UEFA Champions League qualifying. In the 2010/11 campaign, the Slovenian champions were drawn against Dinamo Zagreb. The first leg ended in a 5–1 defeat, but Koper produced an extraordinary response in the return match. Goals from Enes Handanagić, Ivica Guberac and Mitja Brulc gave the hosts a 3–0 victory and left them one goal short of overturning the tie. Dinamo eventually held on to progress 5–4 on aggregate, but the comeback remains one of the most memorable European nights in the club's history.
Koper have also made regular appearances in qualifying rounds of other European competitions. The club played in the UEFA Cup and Europa League and reached the second qualifying round of the Europa League in both 2014/15 and 2015/16. These campaigns gave Koper the opportunity to face clubs from across the continent, although the Slovenian side has not reached the main phase of a UEFA club competition.
The domestic cup has provided another source of major honours. FC Koper won the Slovenian Cup in 2022, defeating Bravo on penalties in the final. It was the club's second triumph in the competition, following its first cup victory in 2010. Koper therefore belongs to the group of Slovenian clubs that have won both the national championship and the national cup.
The club plays its home matches at Stadion Bonifika in Koper. The ground forms part of the wider Bonifika sports complex and has been associated with local football for decades. Koper's distinctive yellow-and-blue colours, together with the nickname Kanarčki, meaning Canaries, are central elements of its identity. The history of FC Koper combines the football tradition of Slovenia's Adriatic coast with the most successful period in the club's history, whose peak remains the championship triumph of 2010.