A flexible budget, also called a variable budget, is financial plan of estimated revenues and expenses based on the current actual amount of output. In other words, a flexible budget uses the revenues and expenses produced in the current production as a baseline and estimates how the revenues and expenses will change based on changes in the output. This is why it’s often called a variable budget. Management often uses flexible budgets before a period to predict both a best case and worse case scenario for the upcoming accounting period. This provides a "what if" look at the future of the company’s financial performance.