The currency of Trinidad & Tobago is the T&T dollar (TTD). Banknotes are available in denominations of $1 (red), $5 (green), $10 (grey), $20 (purple), $50 (olive) and $100 (blue). The dollar is subdivided into 100 cents, with coins available in 1¢, 5¢, 10¢, 25¢ and 50¢ denominations.
MasterCard and Visa credit cards are accepted by most Tobago hotels, restaurants and shops. American Express is accepted in larger hotels, but not widely elsewhere. You are unlikely to be able to pay by card at smaller guesthouses, shops, stalls and bars, especially in the rural areas of Tobago. You will often be asked to provide identification when paying by credit card in supermarkets and stores, so be sure to carry your passport, id or photocard driving licence. This also applies when visiting any of the local banks to withdraw cash or cash travellers cheques.
Many businesses in Tobago will accept payment in US dollars. However, the exchange rate will not be in your favour. It can be a very expensive way of paying for things.
ATM cash machines are often the easiest and most convenient way of drawing cash while in Tobago. However, this assumes that you pay your credit card balance in full in each month and that your card company does not make excessive charges for cash withdrawals.