If you’re moving to Lisbon or Cascais and want an American school, you’ll probably end up comparing these two: the Carlucci American International School of Lisbon (CAISL) and TASIS Portugal. Their campuses are close to each other at Linhó, on the Sintra side of the Serra. Both teach in English from age 3 to Grade 12 and end with the IB Diploma. But they get there differently, charge differently and handle transport differently.
This page sets the two schools side by side, using only their own websites and the official IB, MSA and CIS registers. It doesn’t pick a winner. The right school depends on your child and your plans.
At a glance
| CAISL | TASIS Portugal | |
|---|---|---|
| Campus | Rua António dos Reis 95, Linhó, Sintra | Alameda do Linhó, Penaferrim, Sintra |
| Ages | Early Childhood (age 3) to Grade 12 | Pre-Kindergarten (ages 3–4) to Grade 12 |
| Primary and middle years | American curriculum | Core Knowledge (Pre-K–Grade 8), Singapore Math (K–Grade 8), Next Generation Science Standards |
| Grades 9–10 | American High School programme | Cambridge IGCSE |
| Grades 11–12 | American High School Diploma for every graduate, plus optional IB Diploma (about 80% take it) | IB Diploma Programme |
| Tuition 2026/27 | €12,128 – €23,532 (fee page) | €13,007 – €24,308 (fee page) |
| Lunch | Included for Early Childhood and Kindergarten. €1,212 a year from Grade 1 | Lunch and two snacks included |
| School bus | Yes, at extra cost: Cascais and Lisbon routes | Not included in tuition. The school helps families arrange transport |
| Applications | All year, subject to space | All year, subject to space |
| Run by | Fundação Escola Americana de Lisboa (not-for-profit) | TASIS Foundation (non-profit) |
Curriculum and diplomas
CAISL follows an American curriculum from Early Childhood to Grade 12. Every graduate earns an American High School Diploma. In Grades 11 and 12, students can also take the IB Diploma alongside it, and the school says about 80% do. Students on the American diploma alone take coursework and exams set by CAISL teachers and complete a Graduation Project. High school students can also take online courses, including Advanced Placement (AP), through VHS Learning, with the school’s approval.
TASIS Portugal combines several frameworks. Younger children follow the Core Knowledge curriculum (the school holds Core Knowledge School of Distinction status) and Singapore Math. In Grades 9 and 10, students take Cambridge IGCSEs, on average nine each, according to the school profile. Grades 11 and 12 are the IB Diploma Programme. To start the IB Diploma, TASIS asks for six IGCSEs at grade C or above, including English and Maths. The school’s 2023–24 IB booklet says students who don’t meet that bar can complete a TASIS Diploma instead. The school says its whole Class of 2026 took the full IB Diploma.
In short, CAISL keeps an American diploma track all the way through, with the IB as an option. TASIS uses British-style IGCSE exams at 14 to 16, and makes the IB the main route for the final two years.
Both schools are on the IB’s list of authorised Diploma Programme schools. For how they compare with every other IB school in the area, see IB schools in Lisbon and Cascais, compared.
Fees for 2026/27
Annual tuition, from each school’s 2026/27 fee page:
| CAISL | Tuition | TASIS Portugal | Tuition |
|---|---|---|---|
| Early Childhood – Kindergarten | €12,128 | Pre-Kindergarten | €13,007 |
| Grades 1–2 | €14,060 | Kindergarten – Grade 2 | €17,290 |
| Grades 3–5 | €15,632 | Grades 3–5 | €19,246 |
| Grades 6–8 | €17,756 | Grades 6–8 | €20,028 |
| Grades 9–12 | €23,532 | Grades 9–10 | €23,093 |
| Grades 11–12 | €24,308 |
The year bands don’t line up exactly. Kindergarten is in CAISL’s lowest band but in TASIS’s Kindergarten–Grade 2 band. CAISL’s tuition is lower in every band except Grades 9 and 10, where TASIS charges €439 less.
Other fees at CAISL:
- €100 application fee
- €600 one-time registration fee
- €1,953 building fee each year for the first five years a student attends, from Grade 1
- Lunch from Grade 1: €1,212 a year
- School bus: €3,632 a year round trip, or €1,816 one way
- After-hours care for Grades 1–5: €340 to €1,200 a year, depending on the number of days
Tuition includes a laptop from Grade 1, books, extracurricular activities, and Portuguese and English language support.
Other fees at TASIS Portugal:
- €100 application fee (€150 for Pre-K)
- €5,000 one-time Campus Enhancement Fee from Kindergarten. For Pre-K, families can pay a €3,000 enrolment deposit, which is applied to tuition, instead.
- €750 re-enrolment fee every year
- External exam fees (IGCSE, IB) are extra
Tuition includes lunch and two snacks a day, books, after-school activities, violins for the year groups that need them, and field trips. TASIS gives 15% off for a third child and 25% off for a fourth when they’re enrolled at the same time. CAISL’s full fee schedule sets out its own reductions.
A worked example
These figures use the 2026/27 fees above for a child joining as a new pupil. They don’t include the bus, exam fees or any discounts.
| CAISL | TASIS Portugal | |
|---|---|---|
| Grade 3, first year | €19,497 (tuition €15,632 + lunch €1,212 + building fee €1,953 + registration €600 + application €100) | €24,346 (tuition €19,246 + Campus Enhancement Fee €5,000 + application €100) |
| Grade 3, a following year | €18,797 (tuition, lunch and building fee) | €19,996 (tuition and re-enrolment fee) |
| Grade 11, first year | €27,397 (tuition €23,532 + lunch + building fee + registration + application) | €29,408 (tuition €24,308 + Campus Enhancement Fee + application), plus IB exam fees |
Fees usually change each year, so check both fee pages before you budget. Our fees guide compares these with every other school near Cascais and Lisbon.
Getting there: location and buses
The two campuses are close to each other at Linhó, inland from Cascais and away from the train line. From Cascais or Lisbon you’ll mostly be driving or using a school bus.
CAISL runs an extensive bus service, at extra cost, covering the most populated areas of Cascais and Lisbon. Routes follow the main metro and train corridors. Large 50-seat buses serve the busiest areas, and 8- and 14-seat vans serve more scattered ones. Children are picked up at home where possible, but not every address is covered, so check with the Accounts Office before you sign a lease. The buses have individual seat belts and adult monitors on board.
TASIS Portugal says bus service isn’t included in tuition, but its admissions team is happy to help families arrange transport. Ask what’s available from your area.
For which areas each school’s bus reaches, and what the drive involves, see where families live, by school run.
Campus and services
| CAISL | TASIS Portugal | |
|---|---|---|
| Meals | On-site kitchen with three hot lunch options a day. Snack bar for secondary students | Lunch and two snacks a day, included |
| Sport | Gymnasium, smaller gym and fitness room. No on-site pool | An Athletic Center is planned but not yet funded. No pool |
| Music and arts | Choir and orchestra. Dance studios | Music academy, with violin in the required grades. Dance academy |
| Martial arts | Capoeira (after school, extra cost) | Judo, kendo and taekwondo |
| After school | After-hours care for Grades 1–5 (extra) | After-school clubs and sports included |
| Class sizes | High school: up to 60 students per grade, no more than 20 per class | About 1 teacher to 8 students. Two full-time teachers in every class from preschool to Grade 4 |
TASIS moved onto its site in 2020 and is still building its campus in phases. Its Campus Enhancement Fee goes towards that work.
Admissions and visits
CAISL accepts applications all year, subject to space. You apply online, send three years of school reports and any standardised test results, and pay the €100 fee. Decisions are made by an admissions team that includes the principal and the director. Children must be 3 by 1 September for EC3, 4 for EC4, 5 for Kindergarten and 6 for Grade 1. High school applicants who aren’t yet fluent in English take a language test. When a class is full, eligible children go into a wait pool. Places are then offered in this order of priority: re-enrolling students, children of US government employees, students from American schools, students from English-language schools, and then others.
TASIS Portugal also considers applications all year, using OpenApply. For middle and high school, you send three years of reports, a teacher recommendation and any test results. The school asks for a family visit, or a video call if you’re abroad. High school applicants take the WIDA English test. Grade 10 entry is only possible for students already on the IGCSE. The school considers Grade 11 applicants who plan to take the IB Diploma. Full classes have a wait pool. The school year usually starts in the last week of August.
Open days: neither school had published open day dates when we checked on 21 October 2026. Both offer visits by appointment. Our open days and enrolment calendar tracks dates as schools publish them.
Results the schools publish
| CAISL | TASIS Portugal | |
|---|---|---|
| IB Diploma 2026 | Average 34 points, 100% pass rate, 54 of 54 candidates awarded. 24% earned a bilingual diploma | Average 34.8 points on its IB page (34.6 in its 2026–27 school profile), 98% pass rate. 49–51% scored 35 or more |
| Highest IB scores 2026 | 44, 43, 43 | 44 |
| Other | 86% of students met the SAT benchmarks (2026, College Board) | IGCSE 2026: 54% A*/A, 94% A*–C |
The world average IB score for May 2026 was 30.88. Bear in mind that results depend on who sits the exams. At TASIS the whole class took the full Diploma. At CAISL most students do, and the rest take the American diploma only. A small change in the share of students taking the full Diploma can move an average. Ask each school how its students did overall, not only those who sat the IB.
Accreditation and recognition
| CAISL | TASIS Portugal | |
|---|---|---|
| Portuguese Ministry of Education | Permanent licence since 2003, for an American school from Early Childhood to High School | Authorised through the Direção-Geral da Educação. Grades map to the Portuguese system on the school’s equivalence table |
| IB Diploma Programme | Authorised since 28 May 1998 (IB) | Listed as a Diploma Programme school (IB school finder) |
| US regional accreditation | Middle States Association (MSA): listed as active in the MSA directory. The school says it’s accredited through July 2029 | Not in the MSA directory (only TASIS Dorado in Puerto Rico is). No US accreditor named on the school’s accreditation page or 2026–27 profile |
| Council of International Schools (CIS) | Member. The CIS directory shows “CIS Accredited: No”. CAISL was accredited by CIS and NEASC from 1982 and moved to MSA in 2019 | Member. The CIS directory shows “CIS Accredited: No” |
| Other | Says it’s recognised by the US Department of State | Cambridge International School. College Board code (CEEB) 916614. Core Knowledge School of Distinction |
If accreditation matters to you, for example because you may move back to the US mid-way through high school, ask each school how its diploma and transcripts are recognised where you’re heading.
Which suits which family?
There’s no single better school here. These are the differences most likely to decide it:
- If you want an American diploma for every graduate, with the IB as an option rather than a requirement, CAISL is built around that.
- If you like a structured, knowledge-rich primary curriculum and want IGCSE exams before the IB, that’s how TASIS is designed.
- If you work for the US government, CAISL gives your children priority for places when a class has a wait pool.
- If you need a school bus from Lisbon or Cascais, CAISL runs one. At TASIS, ask what’s available from your street before you commit.
- If you’d rather have fewer extras to budget for, TASIS includes lunch, snacks, books and after-school clubs. CAISL’s tuition is lower in most year groups, but lunch from Grade 1, the bus and the building fee are added on top.
- If your child is joining in Grade 10, TASIS only takes students already on the IGCSE. CAISL considers applicants for any grade if there’s space.
- If US regional accreditation matters to you, CAISL is MSA-accredited. Ask TASIS how it handles transfers to US schools.
The best test is a visit. Watch a class in your child’s year group, ask about the bus from your area, and ask how new students settle in.
Last checked: 21 October 2026. Please confirm fees, transport and admissions with each school before you decide.
Sources
All checked on 21 October 2026.
- CAISL: fee schedule 2026–2027, apply, lunch and bus, High School and 2026 results, Meet us, history and accreditation, facilities.
- TASIS Portugal: tuition and fees 2026–2027, curriculum, IB Diploma, accreditation and memberships, school profile 2026–2027 (PDF), admissions FAQ, admissions policy 2025–26 (PDF), IB Diploma booklet 2023–24 (PDF), school life.
- Registers: IB: CAISL and the IB school finder; MSA accreditation directory; CIS membership directory.