Koh Samui (the full name, with ko meaning "island" in Thai) is located some 80 kilometres off the coast of Surat Thani, about 560 kilometres from Bangkok. It can be reached by air from Bangkok, or by ferry boat from Surat Thani town.

The major access to the island is still by sea, with a large car ferry running continuously from Don Sak to the west coast and passenger craft running between Surat Thani and Na Thon. Buses carry passengers over the ferry, allowing uninterrupted travel between Samui and Bangkok, or Samui and Hat Yai.

By Ferry
Two ferry companies operating from three ferry piers along the Surat Thani coast on the main land and two on Koh Samui

Ratcha Ferry Co.
Operates the vehicle and passenger ferries from the Don Sak pier to the Thong Yang pier on Koh Samui. The ferry departs Don Sak daily at 8.00 am, 10 am,12 noon, 2 pm and 5 pm and the crossing takes one and a half hour and costs about 25 Baht.
From Samui's Thong Yang pier, there are seven daily departures at 7 am, 8 am ,10 am, 12 noon, 2 pm, 4 pm and 5 pm.

Express Passenger Ferry
Songserm Travel operates the express passenger ferries from the Tha Thong pier with 3 daily departures at 7.30 am, 11.30 am, and 2 pm.
Songserm Travel also operates a slow night boat from Ban Don pier in downtown Surat Thani to Koh Samui, departing at 11 pm nightly and reaching the Nathorn pier around 5 am.

The major accommodation beaches, Lamai and Chaweng, are both on the east coast and are lined with bungalows and hotels, though most are hidden among the foliage, allowing the natural beauty to remain intact.