Oeiras International School
International School in Lisbon
Quick answer
Oeiras International School (OIS) serves 463 students from 48+ nationalities aged 3 to 18 across a 5-hectare campus near Lisbon, with a 1:6 teacher-student ratio. The school is an IB Continuum World School (PYP, MYP, DP), non-academically-selective. Accredited by IBO, CIS, NEASC and ECIS. Tuition $14,000-$24,000 per year. Strong fit for diplomatic, tech-industry and remote-work expat families on Greater Lisbon assignments seeking IB-track education with strong personal-growth focus.
Key facts
- Curriculum: IB taught at Oeiras International School.
- Tuition: $14,000–$24,000/yr published in EUR, US$ equivalent.
- Avg class size: 16 (max 16) Lisbon international school · 460 students total.
- 50 nationalities top: American/British.
- Ages: 3-18 school day starts at 8:15.
- Accreditations: IBO, CIS, NEASC plus 1 more.
460
50 (American/British)
16 avg / 16 max
Rolling
IBO, CIS, NEASC, ECIS
About Oeiras International School
Oeiras International School is committed to promoting a respectful community of independent and passionate lifelong learners who are aware of their roles and responsibilities in an ever-changing world. To this end, OIS offers a variety of learning experiences within a supportive and challenging environment of rigorous academic programmes.
| Item | Amount |
|---|---|
| Annual tuition (USD) | $14,000 – $24,000 |
| Annual tuition (EUR) | 13547-21713 |
| Fee year | 2025-2026 |
| True annual cost (with hidden fees)how we calculate | $20,650(+9%) |
| First-year total (with registration + deposit) | $22,150 |
| Cost position in Lisbon | 95th percentile(premium tier) |
Hidden costs & fee notes
Full IB continuum (PYP, MYP, DP). Historic campus in 17th-century palace grounds. 5% discount for 2nd child, 20% for 3rd.
IB
IB Diploma
98% pass rate
Chinese, French, Portuguese, Spanish, German
Varies depending on individual needs.
Yes
English as an Additional Language
8:15 – 15:45
Yes
Yes
Recommended neighborhoods
Oeiras, Carnaxide, Linda-a-Velha, Alges
Is Oeiras International School right for your family?
A School Fit Brief scores this school against your children's ages, learning needs, and budget — with hidden fee analysis, admissions timing, and a ranked shortlist of alternatives in Lisbon.
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At a Glance
Fee Position in Lisbon
Mid-rangeSchool Profile
Class Size
Student Diversity
Very diverse
Common: American/British
Estimated Real Cost
Tuition + registration, transport, uniform, exams
Full IB continuum (PYP, MYP, DP). Historic campus in 17th-century palace grounds. 5% discount for 2nd child, 20% for 3rd.
Decide on this school — and four others
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Nearby Schools (within 5km)
Disclaimer: School profiles are source-backed decision aids, not endorsements or official rankings. Tuition figures are approximate and may not include registration fees, uniforms, transport, or exam costs. Always verify directly with the school before applying. WhereNext is not affiliated with any school listed. This is not admissions consulting, legal advice, or official school placement guidance.