Thailand has strong meditation traditions across multiple Buddhist schools.
Wat Suan Mokkh (Suan Mokkh, Surat Thani) runs the famous 10-day silent international retreat every month, 1st–10th. Free of charge (donation-based). No phones, no talking, daily Dhamma talks. Very physically demanding — sitting and walking from 4am to 9pm. International applicants welcome.
Doi Suthep International Buddhism Center (Chiang Mai) offers 5–21 day retreats with monastic discipline. Donations only. English-speaking instructors.
Wat Pah Nanachat (Bung Wai, Ubon Ratchathani) is the international monastery of the Ajahn Chah Forest Tradition. Daily life with monks. Application required, multi-week stays.
Vipassana Dhura Meditation Center (Bangkok) runs 7-day retreats accessible from the city. Less strict than Wat Suan Mokkh but still meaningful.
For beginners uncomfortable with monastic settings: many yoga retreats (above) include daily meditation. Start with 3 days before attempting 10-day silent retreats.
Bring: loose modest clothing (white preferred at monasteries), no jewelry, mosquito repellent.