IDD (International Direct Dialing) is available from most hotels and travel agents around the island. The outgoing international code is 001 followed by the relevent country code. The cheapest way is to phone from a post office or to buy a 500 baht international phonecard. These cards can be used at public cardphones - usually located outside the supermarket where you can buy a card. Recently the telephone system on Samui has been upgraded and all local numbers are now prefixed by 077.