Ruamrudee International School (Ratchaphruek Campus)

The Ratchaphruek campus, known as RISR, is the second full-age campus of Ruamrudee International School, the Catholic school founded in Bangkok in 1957. It opened in August 2019 on a purpose-built site of about 17,600 square metres off Bang Kruai–Sai Noi Road in Nonthaburi, near Ratchaphruek Road and west of the Chao Phraya River. It began with Pre-K to Grade 5 and added a year group at a time; Grade 12 started in August 2025, and the first seniors graduate in 2026. The campus follows the same philosophy as the older Min Buri campus on the other side of the city, but runs its own admissions and fees.

Children can join at Pre-K 2 (age 2) and continue to Grade 12. Teaching follows an American standards-based curriculum, using AERO standards for English, maths and social studies and the Next Generation Science Standards for science. High school students can take Advanced Placement courses, and RISR is now an authorised IB World School for the IB Diploma Programme. The school is accredited by WASC and is a member of ISAT. English language development and learning support are offered for an extra fee, and the student body is mixed, with a large Thai contingent.

Facilities include a 25-metre indoor swimming pool, shaded rooftop courts, a multipurpose hall, indoor courts for badminton, basketball, netball and volleyball, music rooms, science laboratories, a library and an art centre. For 2026–2027, the combined annual fees are THB 576,000 for Pre-K, THB 734,000 for Grades 2–5, THB 771,000 for Grades 6–8, THB 847,000 for Grades 9–11 and THB 851,500 for Grade 12. These include tuition, a student life fee and, in the younger years, meals. New students also pay a THB 100,000 registration fee and a THB 40,000 learning resources fee.