San Francisco Currency Guide
San Francisco uses the US Dollar.
ATMs can be found all through San Francisco, particularly in the tourist, dining and shopping districts. If you are planning on withdrawing money or using your credit card while travelling overseas, be sure to notify your bank before you travel for security purposes and to check what international withdrawal fees may apply to your card.
Before you leave home, it is important to convert some of your Australian Dollars into US Dollars to have ready to go when you arrive in San Francisco for tips, snacks, cab fare, whatever. US Dollars are available to pre-purchase from Travel Money Oz before you fly minus the fees and commissions.
Before travelling, consider bringing a credit card or travel money card with you overseas instead of carrying large amounts of cash. If you don't have a credit card, a pre-paid Cash Passport may be an option. These cards allow you to access your money in the form of US Dollars from most international ATMs and also use wherever MasterCard is accepted.