The Lisbon IB landscape
Lisbon's IB market scaled rapidly during the NHR-driven 2020-2024 expat wave. St Julian's School (the long-established benchmark) sits at the top, with CAISL and TASIS Portugal close behind. Park International School, Oeiras International and several newer entrants offer credible IB Diploma at lower fees. Cohort sizes are still small relative to Madrid or other European capitals.
The 2026 top 6 IB schools in Lisbon
St Julian's School
The historical and academic anchor of Lisbon's international school market. Long-established British heritage school with strong dual A-Level and IB Diploma sixth-form. Three-year IB average above 35 points. Strong destinations to UK, US and Portuguese universities. The default first choice for IB-committed Lisbon families.
Carlucci American International School of Lisbon (CAISL)
Premier American international school in greater Lisbon. Both AP and IB Diploma pathways. Strong faculty across STEM and humanities. Particularly suited to American families wanting IB optionality alongside US-style curriculum.
TASIS Portugal
Newer entrant linked to the long-established TASIS network in Switzerland. Both AP and IB pathways. Modern campus. Cohort outcomes in early years promising. Best for families willing to take a small bet on a school improving year-on-year.
Park International School
Coastal Cascais-based premium international school. Strong primary feeder leading into IB Diploma. Cohort outcomes have improved year-on-year since 2022. Particularly worth considering for families based on the Estoril/Cascais coast.
Oeiras International School
Full IB continuum from PYP. Newer school with growing reputation. Modern facilities. Strong CAS programme. Worth considering for families wanting an IB-only pathway from primary onwards.
United Lisbon International School
Newer central Lisbon international school with growing IB cohort. Best for families wanting central location and IB option. Smaller cohort sizes; more individualised counselling. Track record short but trajectory positive.
What didn't make the list
Several Lisbon schools offer IB Diploma but with cohort averages below 31 or insufficient outcomes data. Several recently authorised schools will be worth revisiting in 2027.
IB vs. Cambridge in Lisbon
Cambridge IGCSE and A-Level remain widely available at premium Lisbon schools. For globally mobile families IB tends to travel better; for British-curriculum continuity families Cambridge A-Level is straightforward. See our deeper analysis in the IB vs. British curriculum guide.
Fee context
Premium IB places in Lisbon now sit at EUR 18,000-22,000 per year in Years 12-13. Mid-tier IB schools come in at EUR 13,000-17,000. See our full Lisbon school fees report.