Two of Phuket's international schools sit in Kathu district, and they belong side by side when the question is what a school costs rather than which one is grandest. Kajonkiet International School Phuket (KIS) teaches the English National Curriculum. QSI International School of Phuket teaches an American, mastery-based programme and invoices in US dollars. We call them mid-fee because they sit between the island's cheapest schools and its premium ones on the figures in our 2026/27 map of the island's schools. That label is ours, not theirs.
This is a read of what each school publishes about itself, taken on 10 October 2026 from their own websites and fee documents. We have not visited, have spoken to no parents, and report no one's opinion of the teaching. We have no relationship with either school. ZEN Real Property rents villas, which is why the housing section is there. QSI's fees are in dollars; we convert them at 33.57 baht to the dollar, a market rate taken from ExchangeRate-API on 10 October, not a bank quote, so treat every converted figure as a guide that moves with the exchange rate.
The two schools in one table
| KIS | QSI | |
|---|---|---|
| Where | Soi The Valley 1 Village, Phra Phuket Keaw Road, Kathu | 81/4 Moo 1, Chalermprakiat Ror 9 Road, Kathu |
| Ages | Early Years from 2, through Year 13 | From age 2 through Secondary IV (Pre-K to Grade 12, in the school's own 2025/26 profile) |
| Curriculum | English National Curriculum; IGCSE "predominantly" on Cambridge International syllabuses; AS and A2 levels in the sixth form | American-style mastery learning; a QSI diploma earned by credits; four Advanced Placement courses on site and more online |
| Roll | Not stated on the pages we read. Roughly 36% Thai and 64% representing 50 nationalities | About 130 students from 25 nationalities and 25 full-time teachers; 10 students in the Class of 2026 |
| Class size | At capacity, no more than 16 in Early Years, 20 in primary, 24 in secondary | Small by the school's own description; no cap published |
| Accreditation | Full ACS WASC accreditation, valid through June 2032 | Middle States Association (MSA); accredited by the Thai Ministry of Education; member of ISAT |
| Ownership | Part of the Kajonkiet group; the only English-curriculum school in it | Quality Schools International, a non-profit; its 2025/26 profile counts 34 schools in 28 countries |
One discrepancy to record so nobody "corrects" it later. QSI Phuket's own accreditation page still says the group is "working to achieve" system-wide Middle States accreditation. The group's page and the school's 2026/27 information packet both say it was achieved in April 2022. We have used the latter.
What the tuition costs
Both schools publish a full 2026/27 fee schedule. KIS's rises with age. QSI's does not: one price from the five-year-old class upwards, with a capital fund fee added in secondary.
| Stage | KIS | QSI |
|---|---|---|
| Early years, half day | ฿200,000 (Pre-Nursery only) | US$4,600 (about ฿154,400) |
| Early years, full day | ฿285,000 | US$6,600 (about ฿221,500) |
| Years 1–2 / age 5–13 | ฿345,000 to ฿365,000 by year | US$15,100 (about ฿506,900), paid US$5,900, US$4,600, US$4,600 |
| Years 7–9 | ฿408,000 | as above |
| Years 10–13 / Secondary I–IV | ฿425,000 to ฿454,000 | US$15,100 plus a US$1,600 capital fund fee: US$16,700 (about ฿560,600) |
Three things follow from the numbers. QSI is the cheaper school for the youngest children: a full-day place at 2 to 4 is about ฿63,500 below KIS's ฿285,000 for Pre-Nursery to Reception. From five it is the dearer one: about ฿99,000 to ฿162,000 a year above KIS for ages 5 to 13, and about ฿107,000 to ฿136,000 above it in the upper years once the capital fund fee is in. And the gap narrows as the child grows, because KIS's fees climb by stage and QSI's stay flat. QSI's age classes and KIS's year groups do not line up exactly, so compare by the child's age and ask each school which class yours would join.
Two levers shave the QSI figure. It gives US$200 off for each term paid in full on or before its due date and a further US$400 if the whole year is paid by 1 October, a maximum of US$1,000, about ฿33,600. Preschool and scholarship students get neither. KIS gives 15% off the second child's tuition; on a ฿365,000 Years 5–6 place that is ฿54,750 a year. The QSI fee documents we read publish no sibling discount.
What it costs to get in, and to arrive mid-year
| KIS | QSI | |
|---|---|---|
| Application or registration | ฿2,000 application, non-refundable | US$600 registration (about ฿20,100), non-refundable |
| Entrance fee | ฿60,000, non-refundable, once | None published |
| Endowment or deposit | ฿50,000, refunded on withdrawal with one month's written notice by the stated dates | None; no new capital fund deposits are accepted |
| Up front, in total | ฿112,000, of which ฿62,000 is never returned | About ฿20,100, none of it returned |
| Joining after the year starts | Annual fees pro-rated by the weeks remaining | Pro-rated daily, plus the registration fee and a US$900 mid-year enrolment fee (about ฿30,200) for anyone entering after 1 October, preschool included |
For a family arriving in January QSI's entry cost rises from about ฿20,100 to about ฿50,300, while KIS's stays at ฿112,000, of which ฿50,000 is the refundable endowment. Withdrawal terms differ as well. KIS's fee sheet sets out a refund for the endowment only. QSI refunds a term's tuition in full only if the child leaves within five days of its start, and it makes no reduction for absence, home leave included.
What the tuition does not cover
| Item | KIS | QSI |
|---|---|---|
| School bus | One way ฿37,950 a year, round trip ฿72,600. A further 20% to Cherngtalay, Surin, Kamala, Patong, Kata and Rawai | One trip ฿61,750 a year, two trips ฿95,000, the same on all four routes |
| Meals | Compulsory, and the fee sheet states no price | Optional. ฿90, ฿100 or ฿110 by age; the sheet does not say per day, but the figures read as per-lunch prices |
| English language support | Compulsory if the child is below the school's standard: ฿46,000, ฿58,000 or ฿62,000 a year by stage | Intensive English is "included in the standard tuition fee", per the 2026/27 packet |
| Examinations | IGCSE, AS and A Level entry fees billed in Term 2 for Years 11–13; no amounts published | Not priced in the fee documents we read |
| Uniform | No price on the fee sheet | Shirt ฿450, PE kit ฿500, hoodie ฿650, sweater ฿500 |
| Accident insurance | Provided by the school at no charge, up to ฿20,000 an accident | ฿1,500 |
| Residential trips | Billed at cost: ฿5,000 to ฿9,500 in Years 5–6, ฿10,000 to ฿20,000 in Years 7–10 | Not priced in the documents we read |
The English-support line is the one that moves a budget. At KIS it is decided by the school, it is compulsory and it sits on top: for a child in Years 7 to 13 that is ฿62,000 a year, 15% on a ฿408,000 fee. At QSI the same help is inside the tuition, though the school's admission policy also says an older student with little English may need extra years in secondary to graduate. A family arriving with a child who is not yet fluent should ask both schools for the likely figure in writing.
One child, one year, the way most families pay it
Take a ten-year-old who rides the bus both ways and needs no language support. At KIS in Years 5–6, tuition ฿365,000 plus the round-trip bus ฿72,600 comes to ฿437,600, before the compulsory meals, which are unpriced. At QSI, tuition ฿506,900, the two-trip bus ฿95,000, a ฿100 lunch on all 180 school days of the school's 2026/27 calendar (฿18,000) and insurance ฿1,500 comes to about ฿621,400, or about ฿587,800 with the maximum prompt-payment discount. The gap is roughly ฿150,000 to ฿184,000 a year, and it is smaller than that to the extent KIS's meals cost anything.
The learning offer, on what each school publishes
KIS runs a conventional British sequence: the Early Years Foundation Stage from two, the National Curriculum through Year 9, IGCSE in Years 10 and 11, and AS and A2 levels in Years 12 and 13, with English, mathematics and sciences plus a choice of humanities and arts. It publishes its examination results as graphics. The latest on the site are the 2024 cohort's: 43% of IGCSE grades at A*–A and 84% at A*–C. The site lists years back to 2018 and none for 2025 or 2026. No cohort size is given, and several subject cards show round figures, 50% and 100%, of the kind small groups produce. We would read them as a direction, not a statistic. Its scholarship page offers academic, arts and sport awards for Years 7 to 13 with three assessment windows a year; its FAQ describes academic scholarships only for entry at Year 10 or Year 12. The two pages disagree, so ask.
QSI measures a student on mastery of each unit rather than on time served: a student is graded A or B on a unit and revisits it until the mastery grade is reached, so there are no C or D grades, and the school does not rank its students. Secondary students earn credits, and the school offers three diplomas: an Academic Diploma, one with Honors that requires two AP or IB courses, and a General Diploma for students for whom the academic route is impractical. The school is an SAT test centre and teaches four AP courses on site, with more than 30 through the QSI Virtual School. Its published course list names no IB or A level courses. Its 2025/26 profile lists a Class of 2026 of ten students.
Where the evidence is thin. QSI publishes no Phuket-specific examination or university outcomes. The graduate lists on its website are network-wide: one is headed with 389 graduates "from QSI schools around the world". KIS's results are specific to the school but arrive as graphics, a year behind and without cohort sizes. A class of ten is too small to yield a statistic, and QSI does not publish one. Neither school gives a parent enough to compare outcomes, and we have not tried to.
Where each one is going
KIS's website describes a new campus: a 40-rai site in Kathu with separate academic buildings for Early Years, Primary and Secondary. The page gives no opening date and says nothing about fees. The page says the site is "conveniently close to the main road" and gives no address. If you are choosing a house around the current campus, ask the registrar in writing where your child will be in two years. QSI's information packet describes the present site, built in 1990 as the Phuket International Nursery School and sold to QSI in 2000, and mentions no move.
Where to live for either
Both campuses are in Kathu, and our rental book is the quickest guide to what a family pays to be near them. On 10 October 2026 the median three-bedroom villa on a twelve-month lease asked ฿100,000 a month in Kathu (23 listings), with 14 of the 23 at ฿100,000 or less; the median four-bedroom asked ฿125,000 (18 listings). That is unchanged from the three-bedroom median we reported on 19 September in our rent-near-schools study. Of the 1,845 priced, available rentals on our book that day, 1,816 (98.4%) carry a twelve-month minimum, so these are long-let figures. Our coordinates are by district, not by house, so we cannot rank streets by distance from either school.
| District (twelve-month villa lets; Ko Kaeo and Chalong for comparison) | 3-bed median | Listings | 4-bed median | Listings |
|---|---|---|---|---|
| Kathu | ฿100,000 | 23 | ฿125,000 | 18 |
| Ko Kaeo | ฿120,000 | 24 | ฿135,000 | 24 |
| Chalong | ฿110,000 | 89 | ฿150,000 | 61 |
Set against the fees, a Kathu three-bedroom at ฿100,000 is ฿1.2 million a year. One child's tuition is about 30% of that at KIS in Years 5–6 and about 42% at QSI. Where you live also decides the bus bill. QSI's four routes cost the same, and its Bus 5 runs Patong and Kathu; KIS charges 20% more, about ฿87,100 round trip, for six named areas that include Rawai, Kamala and Cherngtalay. Rawai is on the surcharge list, and it is the second-largest district on our book, with 357 of the 1,541 twelve-month villa lets.
What we could not find
- KIS's meal price, uniform price and total roll. The fee sheet calls meals compulsory and prints no number.
- KIS's fee-increase policy. The sheet says fees are "reviewed annually" and "may be subject to change", with no cap or notice period.
- QSI's AP and SAT entry costs, and any sibling discount.
- QSI's fee table in the information packet is set so that its labels no longer sit over their figures. We used the standalone 2026/27 fee-policy sheet, which is unambiguous, and the two agree on every total.
- KIS's 2025 results and the new campus's opening date.
The verdict, on these criteria only
- A British pathway into IGCSE and A level, or a return to the UK. KIS. It is the only one of the two that teaches the qualification.
- An American pathway, SAT and AP, or a child who learns best at their own pace. QSI. Ask which AP and elective courses will actually run in your child's year.
- The lowest tuition for ages 5 to 13, or two or more children. KIS, on the published fee and its 15% sibling discount.
- A child who needs English support. QSI on price, because Intensive English is inside its fee and KIS charges ฿46,000 to ฿62,000 for it. Ask both how long support usually lasts.
- A child under five. QSI, on the published fee. An arrival mid-year costs QSI families a further US$900, so do the sum for your month of arrival.
The housing question comes after the school, never before it. If you are weighing a Kathu house around either one, our long-term rental book carries what is available now and filters by district, with Kathu first; for the island's other schools, start from the 2026/27 schools map.