The club was founded in 1933, receiving the matricule number 2024. Their colours are yellow and blue. They play their home matches at the Het Kuipje. Westerlo are currently a feeder club to Premier League club Chelsea.
K.V.C. Westerlo was founded in the city of Westerlo by students in 1917, and it was named Sportkring De Bist Westerlo. After five years of existence, the club retired. The club Bist Sport was created in 1931 and it changed its name to Sportkring Westerlo two years later. At that time. some players left the club to found Westerlo Sport, the ancestor of K.V.C. Westerlo. In 1939, the club won its league for the first time. Five years later, Sportkring Westerlo and dissident Westerlo Sport decided to merge in spite of the rivalry between the teams, and the new club was called V.C. Westerlo.
It became champion of the Antwerp second division in 1960. Eight years later it played its first season at the national level in Promotion and it won its league to play the third division in 1969. At the end of the season, Westerlo missed a third title in a row, finishing second behind Eupen. The next year, the club was relegated after the playoff and it stayed in the Promotion for ten seasons. The club then underwent two relegations in a row and thus played in the Antwerp second division in 1982–83. Westerlo was then promoted for three consecutive years to qualify for the third division once again. In 1993, the club promoted to the second division and then to the first division in 1997. In 1996, the club added the prefix Koninklijke (meaning "Royal" in Dutch) to its name.
Westerlo plays its home matches at Het Kuipje, which means "The Small Tank" in Dutch. It is believed to be reference to the Feijenoord Stadion that is nicknamed De Kuip ("The Tank"). Its capacity is of 7,982 with 5,556 seats.