Each year the Spreckels Organ Society raises funds to present an International Summer Organ Festival which is currently the largest Organ Series on a single instrument in the United States. The Festival is comprised of 11 to 12 concerts that feature world-class artistry and provide a unique opportunity for the audience to experience the largest open-air instrument in the world.

The Summer Organ Festival takes place every Monday Night from 7:30 pm to 9 pm from late June to Labor Day. Programs feature young first prize winners of international organ competitions, a Silent Movie Night accompanied by the Organ, a Labor Day Classic Rock Concert performed by the only rock band in the world with an authentic pipe organ, a patriotic Independence Day Theater Organ Concert featuring the American Songbook, organ solo performances by world-class artists, and chamber music performances. In addition, the 2024 Festival will include a jazz ensemble from Montreal and an evening of three concertos for organ & orchestra