The accepted currency in Bali is the Indonesian Rupiah (IDR). It's recommended to exchange currency at official money changers or banks to avoid scams and unfair rates. ATMs are widely available, especially in tourist areas, and many establishments accept major credit cards such as Visa and Mastercard. While some businesses may also accept mobile payment options like GoPay or OVO, it's best to carry some cash for smaller purchases and at places that don't accept cards.