Marymount International School London vs TASIS The American School in England
🇬🇧 London · Side-by-side comparison on verifiable public data.
Both carry a public inspection verdict: Marymount International School London is Independent Schools Inspectorate (ISI) "Excellent" and TASIS The American School in England is Independent Schools Inspectorate (ISI) "Met all standards (2023 routine, post-2023 framework)" — a rare pairing where an official quality rating can be compared head-to-head. On cost, TASIS The American School in England has the noticeably lower entry fee — a material difference for budget-conscious families. See the table below for the figures, and verify against each school's own published fees.
Key Facts
| Marymount International School London | TASIS The American School in England | |
|---|---|---|
| Curriculum | IB | American / IB |
| Ages | 11-18 | 3-18 |
| Languages of instruction | English | English |
| Annual fees | Day GBP 39,540/yr; full boarding GBP 66,990/yr (2026-27, incl. VAT) | Day £15,600-£37,170/yr; boarding £69,650/yr (2026-27, inc. VAT) |
| Enrollment | 250 | 646 |
| Boarding | Yes | Yes |
| Inspection rating | Independent Schools Inspectorate (ISI): Excellent | Independent Schools Inspectorate (ISI): Met all standards (2023 routine, post-2023 framework) |
| Accreditations | Council of International Schools (CIS), Middle States Association of Colleges and Schools, International Baccalaureate Organisation (IBO) | NEASC, CIS, IB, ISA |
Strengths
- ✓ISI 'Excellent' Educational Quality outcome (2022) plus CIS, Middle States and IBO accreditation
- ✓Pioneer IB credentials — adopted the IB as its main curriculum in 1979, among the first in England
- ✓Strong, consistent IB Diploma outcomes (37-point average, 100% pass rate, Class of 2025)
- ✓Small ~250-student, multi-nationality community giving high individual attention
- ✓Established girls' boarding option within a values-led Catholic RSHM ethos
- ✓Dual American Diploma plus AP and IB Diploma pathways, giving families genuine curriculum choice in the Upper School
- ✓Triple accreditation by NEASC, CIS and the IB, plus ISA membership and ISI inspection
- ✓Highly international community of more than 70 nationalities
- ✓Boarding available from age 13, with a green Surrey campus close to London and Heathrow
- ✓Dedicated International Section providing English-as-an-additional-language support
Trade-offs
- !No IB Primary Years Programme — provision starts at age 11, so no early-years or primary pathway
- !Very small enrolment limits breadth of co-curricular and peer cohort scale
- !Premium fees (GBP 39,540 day / up to GBP 66,990 full boarding for 2026-27)
- !Single-curriculum (IB only) with no A-level or alternative-pathway fallback
- !Fees sit at the premium end, with full-year boarding at £69,650 and senior day fees above £37,000
- !No published verbatim 'Excellent' ISI grade, as recent inspections use the met / not-met framework
- !Less suited to families seeking a British GCSE / A-Level route, which the school does not offer
- !Quantitative IB and AP results are not prominently published, limiting outcome comparison
Best Fit For
- • Families seeking an all-girls, values-led Catholic education
- • Internationally mobile families wanting a recognised full IB Diploma pathway
- • Students aged 11+ who thrive in a small, close-knit cohort
- • Families needing girls' boarding (full, weekly or flexi) near London
- • American and international families wanting a US-style education near London
- • Students who may relocate within the global TASIS or US university system
- • Families seeking a choice between AP and the IB Diploma under one roof
- • Boarders aged 13-18 wanting a campus close to Heathrow
University Placement
School-reported · not independently verified
School-reported, unverified: graduates are described as progressing to top-tier universities worldwide, with around a third earning a bilingual IB diploma (Class of 2025).
School-reported, unverified: graduates pursue admission to universities in the United States, the United Kingdom and worldwide; specific destination data was not verified from a primary source.
More Comparisons
Frequently Asked Questions
Should I choose Marymount International School London or TASIS The American School in England?
Marymount International School London is best for: Families seeking an all-girls, values-led Catholic education. TASIS The American School in England is best for: American and international families wanting a US-style education near London. The right choice depends on target curriculum, budget, and family priorities — the two are not linearly comparable.
How do fees compare between Marymount International School London and TASIS The American School in England?
Marymount International School London: Day GBP 39,540/yr; full boarding GBP 66,990/yr (2026-27, incl. VAT). TASIS The American School in England: Day £15,600-£37,170/yr; boarding £69,650/yr (2026-27, inc. VAT). Verify against each school's own published fees; some figures are sourced from third-party aggregators.
What curricula do Marymount International School London and TASIS The American School in England offer?
Marymount International School London: IB. TASIS The American School in England: American, IB. Marymount International School London inspection: Independent Schools Inspectorate (ISI) "Excellent". TASIS The American School in England inspection: Independent Schools Inspectorate (ISI) "Met all standards (2023 routine, post-2023 framework)".
Do Marymount International School London or TASIS The American School in England offer boarding?
Marymount International School London: offers boarding. TASIS The American School in England: offers boarding.
Questions parents ask
This comparison is BrightKey's independent assessment using verifiable public data only. University-placement figures are school-reported and not independently verified. BrightKey takes no payments from schools. Our method →