The bus from Bangkok to Koh Samet leaves every hour from the Eastern Bus terminal (Ekkamai). You need to take the bus to Ban Phe which will drop you directly at the Nuanthip Pier from where you can take the ferry to Koh Samet. The buses are operated by Cherdchai tours and are comfortable and cheap. The Bus from Bangkok to Koh Samet Thailand(The bus from Bangkok to Koh Samet) You can also take the bus from the Northern bus station in Bangkok, but there are no direct buses to Ban Phe. You need to take a bus to Rayong from where you then can take a Songthaew for about 20 baht to Ban Phe.