You can change your dollars into Baht in Australia at exchange centres or banks; however, we recommend waiting and changing some of your money at Bangkok International Airport. You will receive a more favourable exchange rate in Thailand, and the changers at the airport will give you a better rate than the hotels. Banks will also have a more favourable rate than the hotels.
Automatic Teller Machines (ATMs) are in all major cities and you can draw money directly through your ATM or credit card, provided it has Cirrus or Maestro on it. Be aware that all Thai ATMs will charge a fee of around 200b ($10) on top of any fees your own bank will charge. Better to draw larger amounts than lots of small ones.
If you still use travellers' cheques, in USD or Australian dollars, they are accepted in all major hotels and banks. Major credit cards (American Express, Diners Club, JCB, MasterCard, and VISA) are also accepted in all major banks, restaurants, hotels, and shops. You will also find that new 'tap on' technology is gaining wide acceptance.
TIP: American Express says that you could pay fees that total 6% or more of purchases if you don't pay in the local currency.
Street stalls and markets are usually best with good old cash.
