TL;DR:International = foreign curricula and English immersion, best for global university routes and higher fees; bilingual = Thai + English mix, regulated locally and less costly; local = Thai curriculum, strongest for local integration and cheaper.
International schools in Thailand teach foreign curricula (British, IB, American), use English as main language, follow international accreditation, and target expatriates and globally mobile families. They offer strong university pathways abroad, smaller classes, and high fees. Bilingual schools combine Thai national curriculum with substantial English instruction (often additional subjects in English), are regulated under Thai law, suit families wanting bilingual fluency and Thai qualifications, and cost less than full international schools. Local (Thai) schools teach the Thai national curriculum in Thai, are the most affordable, provide deep local cultural integration and straightforward Thai university entry, but have less English focus and different teaching styles. Choose by your priorities: global university routes and English immersion (international); balanced Thai identity plus English (bilingual); cost, local integration and Thai qualifications (local). If you have a city and child age, I can recommend specific schools and compare fees, curriculum and entrance steps.
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