Nevada's largest casinos suffered a combined $4 billion loss in 2011.
A report released Friday by the state Gaming Control Board shows 256 casinos grossed $1 million or more in gambling revenue for the fiscal year that ended June 30.
Combined, they had total revenue of $22 billion and posted a net loss of $3.9 billion from the previous year.
In 2010, the largest casinos had a net loss of $3.4 billion on total revenues of almost $20.9 billion.
Total revenue includes money spent by patrons on gambling, rooms, food, beverages and attractions.
The report says revenue from gamblers accounted for nearly $10.2 billion, or 46 percent, of total revenue.
Casinos paid $792 million in taxes and fees, equating to 7.8 percent of gambling revenue.