Uganda’s currency is the Ugandan shilling (US$1 is around USh3800). US dollars are widely accepted for lodging, activities, park entrance fees and safari activities. The dollar bills need to be newer than 2003 and have no tears on them.
Uganda is a cash society: many lodges and restaurants in Uganda don’t accept credit cards, and payment for park fees and permits are in cash, so always have enough cash with you. There are ATMs located in towns across the country, but if you’re travelling to remote areas, it’s a good idea to travel with enough cash to pay for everything you will need.