1963

• ISH was founded as a British Preparatory School

1973

• The school moved to Espoo and became know as the British School.
• Moved again to Töölö
• Later was the school renamed the International School of Helsinki.

1982

• The school moved again and expanded to offer grades 7 through 9 as well as K through 6.

1985

• The school was accredited by the New England Association of Schools and Colleges (NEASC) and the Council of International Schools (CIS)

1990

• The school moved to Kolusaari and added grade 10
• Completed the Five year Report for accreditation

1992

• Grades 11 and 12 were added and the IB Diploma program was introduced

1995

• Completed the self-study for reaccredidation

1996

• Moved to the Ruoholahti site

2001

• Completed the Five year Report for accreditation
• First Strategic Plan was adopted
• Decision to adopt the Primary Year Program and the Middle Years Program of the IB

2003

• Authorized to offer the PYP

2004

• Authorized to offer the MYP

2005

• Completed self-study for reaccredidation

2006

• Fully reaccredited
• Renewed strategic plan (Philosophy, Mission, Vision, Beliefs, Parameters)

2007

• PYP Self Study Report Completed
• MYP Self Study Report Begun

2008

• Reauthorized for PYP
• MYP Self Study Report Submitted
• Renewed Strategic Goals for the next two to three years