The use of foreign bank and credit cards in Myanmar at point of sale is currently limited, although Visa and Mastercard ready ATMs are increasingly widespread in major cities and tourist spots.
The kyat (pronounced chat) is the official currency of Myanmar, abbreviated as K and usually placed before the numerical value (i.e. K500). Kyat come in notes (no coins) of value K50, K100, K200, K500, K1000, K5000 and K10,000.
The US dollar, however, is widely used as an alternative currency, particularly for larger purchases: foreigners are often expected to pay in dollars for hotels, flights, train tickets and access to historical sites. If payment is made in kyat for these transactions, it may sometimes be at a worse rate. When paying in dollars, change will sometimes be given in kyat. Smaller purchases, such as taxi rides, buses and meals are quoted and are almost always paid for in kyat (although some high-end hotels and restaurants quote meal prices in dollars).
Dollar bills should be brought to Myanmar in differing denominations: take plenty of $10, $5 and $1 bills to pay for hotels, flights and historical sites, and take $100 or $50 bills for exchanging to kyat (larger denominations sometimes get a better rate).
Kyat can now be withdrawn using international bank and credit cards in Myanmar, but currently only Visa, Mastercard, Maestro or Cirrus can be used. The biggest providers of compatible ATMs are CB (Co-operative) Bank and KBZ (Kanbawza) Bank. There are no international banks at the moment, and local banks are in the process of becoming part of the international banking system.
There are now over 200 Visa- and Mastercard-ready ATMs in Myanmar, although these are all concentrated in urban and tourist spots - you will not be able to find any in rural areas. Their use is sometimes restricted by internet failure. For ATM cash withdrawals, there is a K5000 transaction fee, and a withdrawal limit of K300,000 per transaction. Depending on the conditions set by your own bank at home, you may be allowed multiple withdrawals per day.