The rules, plainly

Since 26 June 2025, cannabis may be sold only for medical purposes, against a paper prescription on the official form, PT 33. It must be written by a licensed practitioner: a medical doctor, a Thai traditional medicine or applied Thai traditional medicine practitioner, a folk healer, a Chinese medicine practitioner, a pharmacist or a dentist. A prescription may cover no more than 30 days of treatment, and in practice each one is used only once. Only the paper original counts; a photo, a chat message or an email will not do. Bring your passport too.

The age limit is 20, and shops must check it. The rules give extra protection to pupils and students, and to anyone who is pregnant or breastfeeding.

Smoking cannabis in public, whether on a street or a beach, in a market or outside a shop, is treated as a public nuisance under the Public Health Act: up to three months in prison, a fine of up to ฿25,000, or both. Hotels and condominiums set their own rules, and many have a zero-tolerance policy, so check yours first.

Taking cannabis into or out of Thailand, by air, by land or by post, is against the law. Since 17 June 2026, Thai Customs no longer simply confiscates it: it is charged as an offence under section 244 of the Customs Act, with up to 10 years in prison, a fine of up to ฿500,000, or both. A Thai prescription is not a permit to carry it across any border. The US Embassy issued an alert about the change on 8 July 2026.

Driving or riding under the influence of cannabis is an offence under the Land Traffic Act, and the penalties are heavy. For visitors, a conviction can also have visa consequences. If you have used it, leave the car and the motorbike where they are.

Cannabis may not be sold online or through any electronic channel, including websites, apps and messaging, nor from vending machines. A legal sale happens only in person, at a licensed shop, against a paper prescription that the shop keeps on file. Anyone offering to take an order remotely and deliver it is operating outside the law.

Licensed shops must display their licence clearly. You can check whether a shop is licensed on MC-GIS, the public map kept by the Department of Thai Traditional and Alternative Medicine. To report an operator you believe is breaking the rules, call the 24-hour hotline of the Office of the Narcotics Control Board (ONCB) on 1386.