Founded on 23 September 1957, The Overseas School of Colombo (OSC) is Sri Lanka’s oldest internationally accredited educational institution. Originally, named the Colombo School for Overseas Children, it was located at Queen’s Street in Colombo Fort. The founders were from diplomatic missions (British, Burmese, and the Dutch High Commissions) and the business community.

In September 1961, the School leased the premises known as “Rippleworth” at Turret Road (Dharmapala Mawatha) in Colombo 3. In August 1963, the School in Fort had 100 children, while the Upper School at Rippleworth, had about 72 children. In 1967, the School gained accreditation by the International Schools Association in Geneva, Switzerland.

In 1971, the School relocated to 51, Muttiah Road in Colombo 2 (Rivington) until finally in 1983 the School was relocated to its present address in Pelawatte, Battaramulla. During the same year, the School obtained accreditation by the International Baccalaureate (IB) Organisation as an IB World School, capable of offering the IB Diploma Programme. In 1982, the School changed its name to Overseas Children’s School (OCS).

In 1990, the School received further accreditations from ECIS (European Council of International Schools) and MSA (Middle States Association of Colleges and Schools) and over the next five years opened its gymnasium and swimming pool. As the School developed, it became recognised as an office of overseas sponsored school and has built close ties with the US Embassy while maintaining links with the other diplomatic missions. In 1996, the School took its present name, The Overseas School of Colombo. Continuing its campus development programme, the School built a new performing arts facility in 2005, renovated its primary and secondary libraries, and inaugurated a new sports facility in 2009.

At present, OSC is the only school in Sri Lanka to offer the International Baccalaureate Programme from Preschool to Grade 12. OSC is a multinational, English-medium international school catering to the needs of the internationally mobile expatriate community and Sri Lankan students. At OSC we provide an educational setting that is focused on developing each student to achieve their full potential. That degree of personal excellence can only come with highly qualified teachers committed to the needs of all students on a campus which balances nature with state-of-the-art technology, facilities, and resources. OSC is a culturally diverse community with students, parents, and staff working in harmony.