According to the ledger, between December 2014 and January 2015 IS brought in more than $8 million in revenue in Deir Ezzor, an oil-rich province in eastern Syria that's been under IS control since early 2014. But nearly 45 percent of those funds originated from what IS calls “confiscation,” dwarfing all other sources of income like trade, taxes, and oil sales.
“If you miss prayers three times consecutively, then you are going to get your shop confiscated,” Tamimi explained. “If you transport banned goods like cigarettes, they are going to take the money you are carrying.” The vast majority of these confiscations took place on the borders of the province, where IS fighters appeared to be stripping travelers of their valuables to pay for safe passage.
“This document really undercuts IS propaganda,” Tamimi said. “Seeing that they get the plurality of their income from taking things from people — that doesn't put the group in a very good light.”
https://news.vice.com/article/a-leaked-budget-may-finally-show-how-the-islamic-state-makes-its-money