The American Civil War is estimated to have cost the United States government approximately $3.3 billion, which would be equivalent to about $76 billion in today's money. Of this amount, the Union (or Northern) side spent around $2.8 billion, while the Confederacy (or Southern) side spent approximately $1.8 billion. These figures include direct costs such as military expenditures, as well as indirect costs such as interest paid on loans, losses in trade and revenue, and the value of emancipated slaves. The human cost of the war was also incredibly high, with estimates ranging from 620,000 to 750,000 deaths, making it one of the deadliest conflicts in American history.