A key religious leader in Mosul has revealed he is privy to a planned annual budget by the ISIS Caliphate, which envisions their operations for 2015 costing $2 billion, and having a surplus of $250 million.
Details are scant, but it seems this budget is distinct from its war-fighting operations, and simply includes the welfare expenditures and other services they plan to provide across their de facto nation, as the surplus will reportedly be spent on war.
The budget envisions coming up with this $2+ billion from taxation, oil revenues, donations, and spoils of war. As with most governments’ budgets, a lot of the revenue stream seems highly speculative.
In 2014, ISIS gained a major financial boon from looting the central bank of Mosul, which was worth $500 million. Clearly spoils of war were a big positive for them in that case, but it may not be easy to repeat that sort of success.